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For what reasons (if any) would a journal refuse to inform the reviewers about the final accept/reject decision?
I have reviewed several papers for a particular journal in the field of computer science. This journal has the practice of not informing reviewers about the final decision. As an example, I previously suggested a major revision and after a couple of weeks I received the revised paper, then I suggested a minor revision and had radio silence since then (6-7 months ago), so I have no idea whether the paper was accepted, rejected or withdrawn.
To me, it seems like both the decision and the non-blinded, non-private parts of the correspondence should be shared. This seems reasonable given the effort I expended; further, it would be helpful for my future reviews to know whether my review was on par with the others (in terms of both the decision, and the comments). It seems like there is already software that would automate this process (this journal uses Open Journal System as its editorial management system).
Are there disadvantages I am overlooking? What are the arguments for not sharing this information with the reviewers?

One possible rationale would be a belief that the acceptance decision ought to be a confidential matter between the journal and the author, and the reviewers simply don't have a "need to know".
The argument "it is important feedback for the reviewer" isn't very strong, in my view.  Knowing the fate of the paper doesn't really give you much information about whether your review was helpful in reaching that decision, and certainly doesn't tell how you could have made it better.  Conversely, if the editor wants to give you feedback on your review, they can certainly do so without revealing the final decision.
By analogy, consider what happens when you write recommendation letters for people.  When they apply to a school or employer, the school doesn't tell you whether the applicant was accepted or not, because they consider it to be nobody's business except the applicants's (and privacy laws may back this up).  Of course this is a different situation in many ways, but I think the underlying principle is the same - having been part of a process doesn't, in and of itself, entitle you to information about the result which would otherwise be confidential.

Or from a slightly different angle, not just do reviewers not have a "need to know", they also don't really have a "vote to alter the outcome". I can imagine an editor implementing this policy after reviewers complained about the editors' final decisions when it conflicted with their recommendation.

I don't think you should become overly invested in the articles you review. This is similar to other questions I have seen from reviewers about wanting to do a third level of reviews or the like.
You need to de-emphasize your importance in the process.  The primary responsibility for the paper is on the author.  Secondary on the editor.  And only tertiary the reviewer.
Do a decent job on the review but do NOT become invested in the article meeting all of your advice or being stopped (or promoted) based on your review.
Consider your review to be feedback and then move on.

-1 This doesn't answer the question. Also, informing reviewers seems like common courtesy to me rather than an issue of the reviewer's importance.

Are there any reasons why the details of a peer review process should be kept secret from the reviewers?

Yes, it burdens the editor.
Reviewers can ask for---and in my experience will receive---reviews from fellow reviewers.
The outcome of the peer review process will eventually be known to reviewers (with a few exceptions).

Can you elaborate on the first point, what is the burden? How will the outcome eventually become known to the reviewers?

@user3209815 Regarding the first question: You want the editor to do more, that's a burden on the editor. For the second: the manuscript is either published or not, hence, the outcome can be inferred (with a few exceptions).

Exactly :) The info is already sent to the authors, so CC-ing the reviewers is no additional trouble (can be automated). It is of course clear that I can afterwards find the accepted papers, but the missing ones are problematic, are they scheduled for a later date, rejected or withdrawn. And finally, zero feedback makes it hard to improve one's future reviews.

The editor probably isn't sending out mail directly, the system is, so (B)CC-ing is more troublesome. Withdrawal is the exception I eluded to. Regarding feedback, what are you expecting? As I have explained, you can ask for the reviews, which is a form of feedback.

-1 Any decent software will do this with zero effort. I would also like to remind you that reviewing burdens the reviewers.

@Thomas I find your comment rather naive: Software isn't do this and there's a cost associated with implementing. (Burden on reviewers isn't under discussion.)

@user2768 Actually, as someone who's currently using an automated system for editors that does semi-automate the sending of appropriate emails to authors and reviewers, I agree with Thomas. Some software does do this - I'm using it right now. Also, from personal experience, there's a lot more work in reviewing than editing, so it is reasonable to ask editors to spend the minimal effort required to keep reviewers in the loop.


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Is it very unprofessional to contact people from an old job interview and tell them that I think I've made a mistake?
One year ago I withdrew from one job application. I met the committee, the interview lasted nearly 2 hours, they showed me the institution, I had lunch with one of the senior team member. Then I suddenly withdrew before results were announced. The job was in a different country and I haven't got an opportunity to meet anybody again. After some time I see that it was a mistake.
Is it a good idea to send them an email that I regard my actions as a mistake or as unprofessional? Let say to the senior member with whom I had lunch, or to the head of the project.
I have  a feeling that I have made a mistake and it was maybe too harsh to withdraw. Maybe in the future they will seek another sort of collaboration or there will be another job available at the institution.

What do you want to achieve?

By "I've made a mistake" do you mean "I want a job", or something else?  Please edit your question and title to make this clear.

If you just want to stay in amicable terms, and you work in similar fields, then it's very likely that you'll meet in future at a conference somewhere, so you can start the conversation in person more naturally than with a cold e-mail.

I'm going to suggest rolling back your edit -- while the clarification is nice, you have a couple of good answers that would no longer make sense given the edit. I would suggest either (a) adding your clarification below the above text, or (b) opening a new question if you still need advice. Good luck!

Dropping out of a search isn't really unprofessional (unless you told them to go to hell I guess - but then it will be way too late to apologize). In that light, and under the assumption that you just dropped out suddenly and politely (as most people do), mailing them is not so much unprofessional as much as it is pointless. As Henning says in a comment: "What are you trying to achieve?"

Get a job with them? Way too late for this - the previous position is either filled or allocated differently. If a new position opens up, you can always apply again.
Apologize? No need for that - people drop out of a job search for all kinds of reasons all the time. They have almost certainly moved on, and so should you.
Just let them know that you now regret your decision? Why would they need to know this, or even care?
Start a collaboration? "Hey, I dropped out of your search a while ago" is hardly the best ice breaker.

We all make mistakes. It's best to learn to let things go.

I don't see any strong reasons not to do this, but I would turn it around a bit. Rather than emphasizing the apology over the "seeking collaboration", you might consider doing the opposite. If it makes sense to seek some collaboration with them, then you could do that, and then, maybe later, mention that you made a mistake in withdrawing.
I don't know why you use the word "harsh", however. If the words of your withdrawal could be interpreted as insulting in any way then the situation is different and requires a different, fence mending, approach. But otherwise, withdrawal is really just a normal thing, especially if the job was in a different country.

well, my withdrawal was someting like "I see the importance of the project and its goals but I am not interested".

@user3624251 That's not harsh. I am not interested in a lot of important things. No sensible person will hold this against you. (granted, one typically phrases it a bit more indirectly, but whatever)

@user3624251 Well, scientific projects are like pets. Some pet owners are tolerant for people not liking their pets, others are more partial. Unless you know which one is the case, choose your responses accordingly.

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Is TA-ing worth the opportunity cost (of having more time for research)?
If you already have funding, is TA-ing (i.e. being a teaching assistant) worth the opportunity cost of doing more research?
What are the relevant considerations?
I've always heard that focusing on research is a better use of time for boosting one's CV for applying for competitive and research-focused faculty positions, and that they really don't care very much about teaching experience. But recently, I've heard a lot of people saying the opposite.
I'm sure it depends on the field somewhat.
I'm in machine learning, some characteristics of the field which seem relevant are:

It is fast-paced and highly collaborative.
Professors often act more as project managers and don't do as much research.
Successful grad students often publish several papers a year.

In particular, I'm curious about how it looks on a CV, not about other benefits (e.g. learning useful skills)

There is no such thing as 'faculty positions' in general - U. Michigan and Alma College will look for different things on a CV.

Thinking you can do more research with twice the time is like thinking two women can produce a baby in 4.5 months.

@AlexanderWoo It's also highly location-dependent. I guess the advice to only do research comes from US institutions. In Europe you are making your TT job search considerably harder if you have no teaching experience. YMMV.

@PerAlexandersson Efficient researchers work on more than project at a time, which is not the case for pregnancies.

@ElizabethHenning that's true of course, but the brain needs to rest a bit, and TAing is a great way to keep the basics fresh. I never get the good research insights while researching - it happens in the shower or at the gym.

Most people who TA don't have an option as it is what pays the bills and allows them to study. It is less valuable if you can pay your own way.
But it isn't entirely without value. I once held a full fellowship for study (multi year), but it still required that I spend one of those years doing the equivalent of a TA. The feeling was that it is valuable experience for any academic, even at an R1 university. And, FWIW, I actually made more progress after the fellowship ended and I was a "lowly" TA.
But not everyone winds up at an R1 and elsewhere, teaching is more highly valued. And a variety of skills on a CV is, IMO, an advantage, though others may disagree.
Additionally, having something to do other than your research is a useful way to let your mind rest and integrate ideas, which is a key part of learning. And a variety of experiences can be valuable in keeping yourself flexible for the future. And "more" research doesn't necessarily equate to "better" research.
Most doctoral students get along quite well having some duties, such as a TA position, in addition to their research.
But whether it is worth the opportunity cost or not is a completely personal thing. Maybe yes, maybe no. Think about your own needs and resources.

And when this comes up I always feel like mentioning Feynman's own experience, where he found teaching was an essential part of his mental balance and he'd expect to burn out and get no research done if that was all he had on his plate.

Meeting the variety of students is also an inspiration - some make  the day, and teaching experience, so worthwhile...

I think that whether you find instructional duties relaxing or draining depends both on your personality and the duties.

Another potential benefit: I gained a far deeper understanding of mathematical fundamentals when I was a TA and consequently expected to explain them to other people...

Doing research (not just "study") should pay the bills just as well. The fact that, in most (but not all) universities, it pays less, or pays sometimes - is a problem that needs to be resolved.

@zibadawatimmy can vouch for that. Stopped TAin a year ago to focus on research. didn't change my output one bit.

Great answer. On the same theme: having some structured time on one's schedule sometimes makes us more settled in our weekly routine and hence more productive. (The perfect balance is often elusive....)

Also it might just be fun

Absolutely yes. If you have teaching experience on your CV, you can claim that you're good at presenting, you know how to mentor juniors, you have worked with people from other cultures, you are able to work in groups towards a common goal (if you didn't teach alone, which you probably don't as a TA), you know how to manage disputes, and so on. Plus you probably get a lot of examples that you can use to illustrate your skills in an interview.
Of course it's possible the job you're going into don't care about these things, but I can practically guarantee that if you ever need to apply for an industrial job, these things will matter.
For these reasons I'd have TA'ed for free even if my department didn't pay me.

"you know how to mentor juniors"? Normally a TA doesn't mentor juniors but is themselves a junior being mentored. Mostly the same holds for resolving disputes. Which is not to say you can't claim those things on your CV... as long as they cannot check.

All the skills you mention should also be used in research, at least in my field.  This diminishes the value of TA experience.  I know there are some fields where research is largely solitary.

@darijgrinberg A TA is still more senior than the people they're teaching and, as a recent graduate, is perfectly placed to give advice on undergrad matters. If you've TAed and never given your students any kind of advice that could reasonably be described as (minor) mentorship, I'd say you were probably doing it wrong.

@DavidRicherby: I don't remember students ever asking me for advice in my TA days (though I may as well have forgotten). Either way, advice is cheap and rarely impacts evaluations, so in the best case the people reading your applications will know that you have been asked for advice, not whether you have given it and how good it was.

@darijgrinberg teaching itself is mentoring - you are causing someone unfamiliar with the material to understand it. As for resolving disputes, it's common to run into grading disputes as a TA, which you would need to resolve (hopefully by convincing the student that your grading is accurate).

Having a grading scheme is a big step to being able to show consistency of grading...

@AnonymousPhysicist the level of mentoring in research isn't anywhere near the same as in research - in industry, it's fair to assume that you know the answers when you're trying to teach a junior member of the team, and that's more similar to teaching undergraduates than research.

This. Just as a practice for public speaking. Or dealing with adversity. Or pushing back on students wanting their homeworks grading revised. All very useful learning for a professional or research career. I'd value my TA time on computer science at almost as much as one year worth of professional experience. Way more than what it paid.

@Allure Telling someone the answers is neither adequate mentoring nor good teaching.  Personally, I consider research mentoring to be superior because it is typically more extensive and customised.

The penultimate paragraph sounds pretty strange. I managed to get a Ph.D. without much teaching experience, and my clear impression is that this was what sunk all my attempts to apply for tenure-track academic positions. Once I gave up on that and went to industry instead nobody has ever cared about that.

@HenningMakholm What job doesn't require you to manage conflicts? IMO Allure's main point is that a TA position gives you experience in the so-called "soft" skills that are required for every job.

Generally if you can't get the R1 job you expect, the "backup plan" in academia is to move down the rankings, which will increasingly want teaching. This means they will probe you about your teaching experience and preparedness, and at some point places will start asking you to deliver a class to students (which needs to be more than just a one-way lecture of content).
Many answers already address this alternative plan. But fields like CS and statistics have a more common alternative career in industry, with very good reason. So you should consider which direction do you want to have as your backup. In your field it may currently be very easy to get tenure somewhere if you play your cards right. Or you could earn a stupid amount of money, which may be an opportunity you don't see again for a generation. In which case you should look at the TA'ing "cost" as time you could have spent finishing your doctorate up, rather than doing yet more research.
As for the R1's, I'd say the trend is all about funding, far more than teaching.

Being a TA during a PhD is not beneficial.  The downsides are:

A longer PhD at low pay
Reduced research output

The advantages are:

Building teaching experience.  However, since almost everyone has it, TA experience is not meaningful on the job market.  You need to have experience teaching entire courses to be competitive.
You will learn to teach better.  However, most universities are not bothering to properly train their TAs.  Investigate what training opportunities your university has.
You might enjoy it.

My overall advice would be to seek out opportunities to teach an entire course instead of being TA.
Now, if you have the opportunity to be a TA before you get your PhD, that might help you get into a better PhD program.  This could be a much better deal.

Actually, some folks with the TA title do actually teach their own courses. I did. Sometimes you work a more traditional role until you get the experience and they can trust you with a course. But the pay is still low in that situation. But my experience was that higher paid jobs weren't open to students.

since almost everyone has it ... in which case, if you don't have it, it becomes an active disadvantage.

Why would a department let a student just teach a course without first seeing what they can do as a TA?

@Ink blot: At the 4 departments I've TA'ed for (long story), the term "TA" referred to anything from assisting with a large class (together with several other graduate students for each such class) by grading papers and (sometimes) attending lectures and assisting with verifying student attendance, to teaching recitation sections of a large class (sometimes with this you also have the previously mentioned duties), to being entirely responsible for teaching one or two classes, the latter of which I did at all 4 places (at one place my duties were entirely independent teaching). (continued)

However, in all the places I've TA'ed at, as well as those places I've taught at and those places I was an undergraduate student at, one needed prior "partial teaching experience" before being handed the reigns of a class by yourself to teach (e.g. prior experience with recitation sections), or prior teaching experience somewhere else (e.g. a high school teacher leaving school teaching to obtain a Ph.D.), which is essentially what you're saying, except in my experience the term "TA" was used more broadly.

@Inkblot Because it's cheap.

@Allure Nearly all PhD's have a high school diploma.  I have a PhD but I do not have a high school diploma.  I am not at a disadvantage.  This personal experience is why I am skeptical of the value of TAing.

@AnonymousPhysicist it's not completely comparable though - a PhD supersedes a high school diploma, once you have a PhD the value of your high school education, Bachelor's, and even Masters degree drops a lot.

@Inkblot: In grad school, I had a TA position. First semester was just grading, second semester and later I had my own class.

In answer to your very limited question, in evaluating CVs for competitive research focused faculty positions, no one cares if there is a teaching line on your CV. But to the extent that your teaching statement/philosphy is part of your CV, then being able to point to your teaching experience in your teaching statement matters a lot. The vast majority of competitive research focused faculty positions require your to submit a teaching statement/philosophy. While most search committees for competitive research focused faculty positions don't really care about the teaching statement as long as you don't make a fool of yourself, not being able to highlight personal teaching experience is a sure fire way to write a crappy teaching philosophy.

Sure, but in that case the bar for what counts as highlightable personal teaching experience is pretty low.

@ElizabethHenning yes, the bar is pretty low, but there is a bar.

“in evaluating CVs for competitive research focused faculty positions, no one cares if there is a teaching line on your CV” — Maybe there are a few positions where that’s true, but at least in my field (maths), that’s only the absolute extreme top of the job market.  Most jobs that would be described as “competitive research-focused faculty positions” still carry some teaching expectation, and having no teaching experience at all on the CV would (at least in places I know) be viewed as a non-negligible shortcoming.

TAing is great, but it's a law of diminishing returns.
If you have never been a TA, or have only done so once, you may well want to do so again. Having something concrete to point to when the discussion turns to teaching will help your CV. Others point out that TAing will have many benefits besides your CV, though your question specifically excludes such considerations.
On the other hand, if you have already been a TA a few times, your CV will gain very little from additional TA experience. Being the instructor of record would be more significant for your CV. Getting additional high-quality publications would be even better. Though extra time will not linearly correlate to more publications, it certainly won't hurt (that's why pre-tenure faculty at R1s usually try to negotiate teaching release).

I know you said that you are only asking this in relation to the CV appearance, not in terms of skills learned, but the two are fairly interchangeable (depending on where you are applying) Being a teaching assistant teaches you different things from what additional research would.

It teaches you more about a subject. It is easy to think "oh yeah I know SQL/ intro to microbiology/ microeconomics/ whatever", but you will likely have forgotten much of the theory and niche applications of whatever course it is. Teaching it forces you to revise the subject and gain a greater appreciation of it.
Being a TA gives you experience of how to relay ideas to others. It goes without saying that this can have vast real world applicability.
Being a TA can give insight on how to be personable, how not to alienate others, how to engage effectively. This is separate from just coherently explaining an idea (like above), it is doing so in a way that does not sound patronising. This is one of the areas, in my domain, where I see most TAs commonly fall down.
TA work usually involves corrections. This can give you a clear insight what areas inexperienced people in this domain repeatedly fall down in. If something is unintuitive for your students, it is probably unintuitive in the real world too (even if they shouldn't you may see the same mistakes crop up in industry).
More advanced TA positions may involve management, even perhaps to the extent of developing assignments and course material. This level of responsibility has clear benefit in terms of work experience. As a side note it will also give you insight into how people think, and what can be demanded of subordinates (junior TAs) and of students.

Of course this all presupposes that one learns from the experience.

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How can I deal with claims of technical difficulties for an online exam?
I was talking with some instructors, and we noticed that there is a pattern of claims about technical difficulties. I wonder if there are any rules to follow of whether to allow or don't allow students to retake exams. My university and department have not set any such rules.
For example, don't allow to retake the exam unless the server is down for all students. Or allow to retake a new and different exam, but students should share their screens with the TA or instructors.

An opinion. I think such difficulties are currently pervasive and you don't control the system end-to-end. Those with outdated equipment or bad internet access (read economically disadvantaged) are worse off. You probably need permissive rules at the moment. If we live with this structure for a few years we will learn how to do it properly, but at the moment it is a train-wreck.

Since I have spent more hours a day in video conference calls over the last 8 months than I ever though possible, using any one of a half dozen apps my observation is they all fail in both old reliable as well as new and novel ways. Some days all is well. Some days our internal calls just fail. Some days when I'm on site the connections are lousy, but off site they are fine. The reality is that there are plenty of technical difficulties, often exacerbated by slow connections, and you (the university) need to figure out how to deal with them in a lenient fashion.

I think the only real answer to this is "design your assessment so that intermittent technical issues are less likely to cause critical difficulties" - e.g. assignments rather than timed exams.

Please don't reply to requests for clarifications by adding comments.  Instead, [edit] the question to make it self-contained and to address the feedback you've received.  We're trying to build an archive of high-quality questions and answers for the future, and we don't want people to have to read the comments to understand what you're asking.

I would say that most if not all students have access to a video recording device such as a phone or tablet. It should be part of the school's or your guidelines to encourage students to actually record technical difficulties.

"should share their screens with the TA or instructors." If you are trying to stop cheating I think you will find this is a rabbit hole that no-one has found a particularly good solution for.  Really, the solution is a radical transformation away from testing as a measure of learning.

@MonkeyZeus if someone is just trying to avoid taking the test all they have to do is unplug their router.  This is what I mean by rabbit-hole.  Just look at the proctoring solutions some unis are turning to and the disasters they create.

@Buffy: It's not just the economically disadvantaged.  I'm hardly that, but still have occasional problems with sites that assume that everyone uses Windows and Internet Explorer.

Whether set by the university ( @user111388 ) or by the individual course syllabus, I've never taken an online course that didn't contain the "it is the student's responsibility to ensure reliable connection / compatible hardware & software / etc." disclaimer.  To be fair, though, those were pre-pandemic courses designed from the start to be taken remotely, and presumably with more time for careful technical setup & testing from the university's end...

@Buffy no doubt things can and should be improved, but if the power and/or internet is out at my house then I am not taking the online exam now.  I do not see any economically feasible way to guarantee 100% reliable performance.

@emory, yes. That is why we need to "think different". The answer of Neganova points in a useful direction.

Unless we somehow want students' grades to reflect the quality of their home Internet connection, the quality of their hardware, and their tech savvy (or their families'), there is not a sane alternative but to take seriously essentially all claims of technical problems. No, it it not really possible to "prove" technical problems, nor is it reasonable to try to insist that people with technical limitations be astute enough to document the tech problems!
Yes, from a traditional enforcement-oriented viewpoint this is "impossible". Yes, indeed, so, manifestly, that traditional adversarial viewpoint is not really (meaningfully) sustainable in plague times. So, indeed, what instead? Very context/culture -dependent, to begin with. Are classes gauntlets to be run [meaning adversarial situations in which one proves virtue by survival]? Or do we want classes to be fundamentally educational opportunities, and helpful to the students [as opposed to skeptical and adversarial]? In plague times, at least, what are viable (and useful) goals?

What does "goals" refer to (in Goals???)? Classes (goals in themselves)? Exams? Or more generally, the entire education system?

I suppose this is rather off-topic, but a different individual mentioned at the end of their post that project-based learning may be the best of all solutions. Speaking from personal experience, for whatever that is worth, I have very fond memories of my project-based curricula and indeed really believe that I learned the most from them. A project-based course in a certain undergraduate course put me on the trajectory to study that topic at the graduate-level.
By contrast, my more traditional courses – bluntly, those that taught more basic concepts that had to be mastered and recited on homework and exams – are far less memorable. Although the foundation they provided for the more advanced courses was surely useful, I do not believe that they require one to parse and understand the content as clearly and carefully as successful project-based curricula. Of course, what a successful project-based curricula looks like will vary greatly from domain to domain and may not even be feasible given the size of some classes and resources available. So I suppose this is more of a shoot-for-the-moon solution.

I strongly agree, though the main obstacle to this is student complaints that the course is becoming more difficult to avoid cheating, which isn't fair to them. That's a justified concern. But of course, students then complain that not enough is being done about cheating when the course is kept the same. Catch 22, tough situation all around.

Project-based learning is good but doesn't guarantee that the work is done by the student. Exams remain the most used way.

Technical difficulties exist. More noticeable the more important the action they are impeding.
On the other hand if they only suffered a minor issue (if any), it could be great to have an excuse to retake an exam they did poorly!
The issue should be approached much earlier than the exam. First of all I would do a full test a few days before. And by full test I mean that it is setup exactly the same way as in the online exam. Even if it's the same platform used for the rest of the course 'with some minor changes', as those might make it no longer work. Or some intervening update might have broken it precisely that day. For example, it would be somewhat riskier than other  to plan an important exam the second Wednesday of the month (Microsoft release Windows updates the second Tuesday).
Also, the user may not have been able to test the platform on its own. They may not be able to log in to a room like the one that will be used. The program could crash when talking with other people. It might work for them except when there are many people connected at the same time. They may not be aware that their microphone is not functioning/too low without someone at the other end.
It is also very important to make crystal clear what they should be expecting, e.g. the instructor will be sharing a screen and explaining orally what you must do. You must be viewing their screen, you must hear their instructions, your microphone must work (it will be tested when doing roll call at the beginning) and you shall share your desktop; and what they need to do if any of them fails even in the slightest way, such as calling xxxxxxxxxxx where HelpDesk (or some TA/instructors) will be ready to help them.
Some issues will be simple helpdesk calls (tell the user how to unmute/change volume, describe where button X in the new interface is located), others will depend on external factors such as their connection, and other will be even driver related such as the hardware not being detected properly (no microphone listed, sharing produces a blank screen...) up to completely head-scratching issues.
As an instructor such service serves a double purpose: (a) it helps fixing the minor problems (b) documents the existence of the error. A student that calls you in the first 5 minutes is likely to have a genuine problem. Whereas one that only tells you about that a week later would be met with more suspicion. You will need to actively request errors to be reported, though. You may also want to include it in the exam as 0-point "feedback/suggestions" question (or one showed after finishing). Even if they weren't much affected, you might find things to polish/improve (e.g. setting deadlines of 23:59 rather than 00:00 really improve usability, with almost zero effort. But you need to realize the problem caused by the software showing / users noticing only the day it must be turned in).
Plus, it actually provides a better service and helps the students be more confident in that the technology won't ruin their exam. Then, with more data you will be able to make a better decision. Or even accommodate for the issue on-the-fly (such as having the user joined by phone).
What you definitely don't want is to discover when the exam is about to finish that several students were unable to view the instructor screen [where needed data was provided] during the exam, as they were joining via web interface -the screen only showing on the native app- since the app wasn't opening the room for them!
Even when having two identical installs, on identical hardware, you may find one user is unable to perform an action (such as sharing the screen) which works perfectly for the other. Computers are that funny.

PS: You suggest "allowing to re-take a new exam but have students share their screens" but (a) I don't think that will really avoid someone determined to cheat and (b) if it does help keeping people honest for the exams you do, that should already be happening in the original exam. Another interesting possibility would be to allow an optional re-take for everyone.

Yes to the last sentence. Where I am, there have to be at least 4 exams per course. People can take any one of them. Don't know why this is often viewed as bad or impossible.

I have been teaching online for many years and used many LMS versions. In my experience, all of the mainstream systems, Blackboard, Canvas, Moodle, ... and even the older versions like WebCT and eCollege are supported via the use of a commercial quality database system. I wrote this because it has also been my experience that systematic technology problems and errors are captured in the data logs.
The result is a record that can be accessed via the system administrators, which a school could utilize to confirm widespread issues. More important though would be that any mainstream system would have online technical support that would also be used to verify and head of any issues. All that said, I don't recall ever having to check the logs or even help desk records for a systematic failure.
There is always the occasional technology issue, and the best policy is a preemptive one. In other words, plan for the event, create a policy, stick to it, and update it when necessity forces the change. Along with the policy, create a well thought-out support system with processes for the issue during testing.
Finally, in my experience, project-based learning is the best of all solutions (a subset of problem-based learning), where testing is not relied on to measure achievement, but learners are required to demonstrate real-world solutions to actual problems.

The first part of your answer really only applies if technical issues occur on the course platform. Students are just as likely to encounter technical issues on their end which may be no fault of their own.

agreed, it does assume an LMS bee used.  However, in the case of an exam given to large numbers, would it not be probable that an LMS be used. The question used the term, multiple instructors, and the term server. Leading me to think LMS. IN my experience the LMS is almost ubiquitous in higher ed today.

Yes, but even if you use a LMS that does not mean technical problems are with the LMS. If a student is not able to connect due to issues with their own ISP, the LMS will not have any record of this.

also agreed, which is why I stressed the support angle. Like most things in education, answers are almost always complex and require designed solutions that deal with micro issues.

Also remember that most students have consumer devices and consumer internet. Consumer products are less reliable that business products and are cheaper. You really can't expect the same level of reliability as the (old) computers in the actual classroom


text:
Is it ever ethical / justifiable to award additional points to prevent too many students from failing course?
Is it acceptable, if too many students in the class would fail otherwise, to award additional points across the board (in the one class, in one semester)?
Would it require approval of the Division Dean? How could this be justified?

This question is begging an entirely different question: why are so many students failing? Is the course too hard? Is there something wrong with instruction? What would cause such a thing to happen? Dealing with the problem this semester is a bandaid if this happens repeatedly.

I agree with you in that there is a bigger question at play with a situation such as this; however, my question stands. I have knowledge of this occurring and am wondering if others have encountered a similar situation.

Are you asking if it is acceptable to curve grades?

This has happened in many, many classes I was in. Usually the teacher just made an ad hoc decision to (for example) increase all grades by X%, or score a certain question as a bonus point. In particular, no approval of any sort was necessary. This may be different at different institutions.

@Austin Henley:  No, there is no "curving" of grades allowed in this course; program policy. This was done for the sole purpose of preventing too many students from failing the course.

@Onsager:  How is this not considered arbitrary grading? My understanding is that all students were awarded an additional 5 points on the final exam.

So... no curves are allowed because it keeps lots of students from failing, but this year the result is that lots of students are failing?  What changed?

I don't think we can answer this question.  In most cases (at least in the US), the instructor of a course has wide latitude to determine how letter grades are assigned, consistent with the syllabus as distributed to students, and general principles of fairness.  If, as it seems, higher authority has restricted your latitude in this regard, then you will have to talk to that authority to determine what latitude you do have.  Maybe you have to talk to your dean, maybe not.  It completely depends on your internal policies and politics.

@JAnderson: Out of curiosity, what percentage of exam passes do you consider acceptable? For instance, in my courses, I consider reasonably good a percentage of passes between 30% and 50%; more than 50% is rare and there is a problem when it falls down to 10%-20%.

This has always bothered me and is a strong reason why we have stereotypes like teachers pet. Curved grades and teachers defending their potentially poor teaching pattern needs to be fixed, not artificially changed. The best solution I've seen was in tests if an extreme quantity of people got a question wrong, it was thrown out. People who would have got it correct basically canceled out another incorrect answer.

I agree with others that more info is needed.  On what basis was it determined that "too many" people are failing?  I know of many cases where, say, a professor created a midterm exam, many students failed, and on reviewing the exam the professor then realized that it was indeed too hard.  In such a situation, various sorts of curving or point-adding may take place, and no one sees a problem with that.  There's a difference between A) the students really did not learn the material as required; and B) they did, but the mapping of their learning to "points" was faulty.

Instead of asking if this requires approval of someone in particular (which likely varies by institution) a better question (for this site) might be is it ethical (as your second question 'how can it be justified').

@JAnderson: In this question and another one, you have not included enough detail to allow for really insightful answers.  Are you asking about curving grades in general, or about a specific course? In the latter case, you need to give more information about the details of the situation if you want to get anything besides general answers.

I would say, in nearly all cases*, it's unethical. Specifically, if a student's submitted work does not fulfill the requirements for a passing grade, then they do not deserve a passing grade. Arbitrarily adding points that do not reflect the quality of submitted work makes the grade partially or completely useless as an indicator of performance in the class, and if it's not good for that, what's the point?
However, unethical does not necessarily mean unacceptable. Don't get me wrong, I think it should, but I'm not going to impose my moral standards on your grading scheme. Ultimately nobody on this site can tell you whether it's acceptable to do this. Your superiors at your educational institution might be able to, since they'll at least know whether it would violate any of the institution's rules.
In any case, as a few people have mentioned in the comments, arbitrarily adding points to keep students from failing is a band-aid effect. The fact that too many students are failing indicates that there is some deeper problem. Perhaps your teaching is inadequate. Perhaps your grading standards are too harsh. Perhaps the students are not properly prepared for the class. Perhaps your idea of what constitutes "too many students failing" should be revised. And so on.
*Speaking of harsh grading standards, this is (the?) one case in which I think it is ethical to add points: to compensate for an overly difficult exam or assignment. This is a little tricky to get right, though. You have to have a preexisting standard to measure whether the exam is at an appropriate difficulty level. For example, in classes I've TA'd for, there has been a longstanding policy that any time the average grade on a test (across ~1000 students) is less than 70%, it will be taken as an indicator that the exam was too hard, and therefore enough points will be added to everyone's exam grade to bump the average up to 70%. Given the large class size, I think this is reasonable.
For smaller classes, you have to consider the possibility that you just have an underachieving group of students one particular year. In another (small) class that I took, each year the instructor would compute the distribution of all grades in the class over the previous ten years, compare that to a desired target distribution, and make the course material for the next year harder or easier as needed. From what he told me, it gave pretty consistent results. I think this is a good way to do it.
The key is that you have to have a preexisting criterion for when points will be added. If you look at the grades after the fact and decide, hey, too many students are failing, let me add some points so we all look better - then you're doing it wrong (IMO).

+1 for this. I'll add a situation where I think changing scores after grading is acceptable. We once had a Final where most students did well or ok on most problems but almost nobody solved problem 7, but some people went off in a totally wrong direction. The TAs who hadn't seen the question before also thought it strangely worded. Because of this, the Prof. decided to turn it into a bonus question. The grades looked much better after that but very few people went from failing to passing. Yes, he did take the previous year's distribution into account but that wasn't his reason for the change.

I think the first paragraph is strongly worded, although the later paragraphs soften it. I would usually view "the requirements for a passing grade" as certain levels of mastery of the course material. Grades measure this level of mastery only indirectly, and with a significant amount of measurement error. Numerical grades can give a false sense of objectivity and precision to the grading process, especially in the American A/B/C/D/F system.

@OswaldVeblen (late response) indeed, it was my intent to use strong words. I think they are called for here. Also, of course in an ideal world a grade measures mastery of the material, but in practice we usually set up some objective criteria that we take to be a proxy for mastery of the material. I take the latter view of grades in my answer, i.e. the pragmatic one where the grade is based on the quality of submitted work, and I choose to ignore the fact that this is an imperfect test of mastery because I think that fact is not relevant to my answer.

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text:
Years ago, a professor agreed to write a LOR, but never sent it. Therefore, I'm not accepted in any school. What can I do?
Years ago, a professor agreed to write me a recommendation letter.  So I applied to many grad schools indicating him as one of my referees.  However, I didn't find out until later that he didn't write the letter.  Thus, none of my applications were completed, and there were also substantial financial losses due to application fees. I was poor, so it was a big loss for me.
What can I do in this case?  Could I find any justice anywhere?  I just felt hopeless when a tenured professor does something unethical (not criminal conduct); there is nothing a student can do.
[added the following on June 24, 2014]
He recently became a faculty at the university where I am a student (He was at a different university before). I want to forget about what happened, but the damage was too much for me to ignore. And I feel anger whenever I think about what happened.
One remedy would be he takes me on as a PhD student, or provides funding so another professor can supervise me. However, my application was rejected.
I raised my concerns with the dean of faculty of graduate studies, and will meet one of the assistant deans soon. How should I approach this with him/her?

"Years ago, a professor agreed to write me a recommendation letter. So I applied to many grad schools indicating him as one of my referee." Just to clarify one point: are you sure that his opinion of you today is still as high as it was "years ago" when he agreed?

He recently became a faculty at the university I am in.(He was at a different university before) I want to forget about what happened, but the damage was too much for me to ignore. And I felt anger whenever I thought about what happened. One remedy would be he takes me on as a PhD. student, or provide funding so another professor can supervisor me. But my application was rejected. I raised my concerns with the dean of faculty of graduate studies, and will meet one of the assisted dean soon. Do you think the dean can solve the problem and give me some justice? How should I talk to him/her?

Wait!  You "...applied to many grad schools indicating him as one of my referees."  Did you tell him to which schools you had applied?  Did you furnish him with the referee forms?  With the addresses?  "Many years ago" this would likely have been all on paper.  The student has work to do other than just listing a professor as a referee.

Time to move on.

It's now been seven years since your original post. How did things turn out for you?

That sounds like a frustrating and discouraging situation.  Whether you have any recourse may depend on the system.  For U.S. universities, there's not much you can do, since applicants are generally considered responsible for monitoring whether their applications are complete and reminding letter writers.  However, these cultural issues might vary internationally.
One puzzling aspect of your question is that you describe the professor as deceiving you and acting unethically.  Without some specific evidence, I'd assume it was forgetfulness rather than deliberate sabotage.  Forgetting to submit letters is still irresponsible, but not as bad as intentionally not submitting them.
If you have compelling evidence of sabotage, it would be worth bringing to the attention of the university administration.  However, it's not clear to me what sort of evidence you might plausibly have.
If it's a matter of forgetfulness, things are murkier.  If there's a pattern of irresponsibility, then the department head might want to know.  On the other hand, a single incident would probably be ignored.
What makes this tricky is that professors get asked for recommendations in all sorts of suboptimal ways, such as a brief hallway conversation while both people are rushing to get to class.  It's easy to forget under these circumstances.  That doesn't make it right, and responsible letter writers will try hard not to overlook requests.  However, some circumstances make it more understandable than others.  If you do file a complaint with the administration, you should make the circumstances clear.  (But without evidence of dramatic or recurring irresponsibility, I'm not sure it would be worth the effort.)
Have you tried asking the professor about it?  It's too late to fix your applications, but you deserve an apology.  Furthermore, he may have forgotten about it so completely that he doesn't even realize this happened, in which case you'd be giving him a valuable warning that he needs to be more careful (and you might save future students from this problem).

+1 for the forgetfulness angle. @monika, what you describe is very common. Typically, the onus is on the graduate student to ensure the professor submits the letters. After all, it is in your best interest that he does so; he has no incentive to do so, other than because it's the right thing to do.

I'd suggest telling someone in authority about the situation, even if you think your case is an isolated incident. For all you know, there could have been other instances, where the "victims" also assumed it was an isolated incident. If everybody makes that assumption and therefore doesn't bother to report it, a serious problem can go undetected. (P.S. When I was a grad student, applying for my first job, one of my letter-writers apologized to me for not yet having written his letter; this was after I had been offered the job at Michigan (where I still am today).)

"without evidence of dramatic or recurring irresponsibility, I'm not sure it would be worth the effort" - not specific to academia, but if the university receives a series of complaints from people whose applications have been undermined by this person, then they can worry about evidence of recurrence, not each individual who complains. I suppose the problem is that only a small proportion of people whose applications are rejected will learn that this missing reference was the problem, if the institutions they're applying to refuse to tell them what was missing.

I'd like to pick up something that eykanal has mentioned in a comment, because I think it's crucial.
Brace yourself, you're not going to like this. But it's better you know the truth.
When you ask someone for a letter of reference, and they agree, it's up to you to do what you can to ensure that they write it and submit it.
Sorry, that's not what you wanted to hear, is it? But it's what you needed to hear.
So, what can you do if you didn't succeed in ensuring it got written and submitted?
There's exactly one thing you can do: learn from the experience. Now you know, that if you don't put the effort in to ensuring the recommendation letter gets written and sent, that may not happen.
If you want to take it further, here's what you need to do.
You need to broaden the lesson to be taken from this unhappy experience. The broader lessons are (and these apply both within and beyond academia): you often need to manage your manager; and if you need something doing, and you delegate it, you're still responsible for ensuring it gets done.

Professors are busy people. This person's failure to make good on the promise of a letter could be due to a variety of reasons, being a "jerk" being only one of several possibilities. It could be just forgetfulness, or perhaps they wrote the letters but didn't include the correct postage, or the mail got stolen from the mailbox where they dropped off the letters. Things happen, and sometimes we are too quick to find fault. Being absent-minded is not an excuse, but lack of malicious intent definitely impacts the validity of accusations.
Therefore, I would tread lightly and first ascertain the reason. If you really need closure on this, the best way is to NOT talk to the associate dean, but to discuss this with the professor privately, and very VERY politely. Do your absolute best NOT to come across as being accusatory, pursue not the person but the objective facts -- as a student in this department, you are in a much more vulnerable position than tenured faculty, and should account for this in your decisions and actions.
Drop by during this professor's office hours, sit down calmly, and in a polite, humble tone simply explain what has happened years ago.
Do not say "but you never mailed those letters". This immediately puts the person on the defensive and the conversation will quickly devolve from constructive feedback to denial and conflict.  This will have zero benefit for you, but can have negative consequences down the road in ways that are difficult to anticipate right now.
Instead, one approach is to say: "It appears that the letters from one of my references were not received by the institutions to which I applied, and I am trying to figure out if this was through a fault of mine, perhaps lack of clear communication on my part about what I was requesting. I feel uncomfortable talking about this, but I just wanted to see if you had any recollection of that situation and whether you recall any challenges with providing those letters. This will be very helpful to me in understanding how to improve the way I solicit recommendation letters for future fellowship or employment applications."
This interaction presents a great opportunity to learn whether you did, in fact, do something that may have contributed to the unfortunate outcome of receiving no letters from this person. Was it a miscommunication about the application timeline, addresses where to mail the letter, or something else? Chances are you will have to solicit letters again in the future, and knowing what caused the malfunction in the process back then can help you prevent the same issue from happening in the future. What a great opportunity to learn from the past and improve future results.
As @EnergyNumbers noted, "When you ask someone for a letter of reference, and they agree, it's up to you to do what you can to ensure that they write it and submit it." I absolutely agree. You needed those letters, not the professors. Therefore, it was your responsibility to follow up and confirm whether they had mailed the letters you requested. That's just how this stuff works. For this reason, if anyone should be blamed for what happened, it's not the professor. For this reason, I would disagree with @Anonymous Mathematician's position that "It's too late to fix your applications, but you deserve an apology." I would agree that you might deserve (I would say, not deserve, but "benefit from") a brief explanation of what happened. But whether to apologize for this or not remains to be seen, and should be up to this professor to decide. It's their conscience, let them find the course of action that they find acceptable. If this is at odds with your notion of fairness and justice, well, the world does not have to operate in accordance with your notions. Everyone has different ideas of what they deserve, and sometimes letting go and adjusting one's expectations is a much wiser strategy than pushing to get what one believes is their fair share, or fishing for apologies. Letting go is not easy, and absolutely should not be the rule for all situations in life. But the ability to discern what situations warrant letting go are a sign of good discretion and wisdom.
One alternative: As @RoboKaren noted in a comment to OP, it is unclear that "One remedy would be he takes me on as a PhD student, or provides funding so another professor can supervise me" actually represents a remedy. For what? Financial compensation? If this incident occurred years ago, I would consider this, as economists might call it, "sunk cost." If the expense was not recouped in time, or arrangements made for future reimbursement, for all intents and purposes it is water under the bridge. I highly recommend to let the financial aspect go, especially since the amount is probably not nearly enough to justify all the problems such accusations could cause for you while you are trying to remain on good terms with the department's faculty, who hold the keys to your degree.
On the other hand, if the remedy is meant for your ego rather than wallet, then it seems counter-intuitive that much good would come from trying to renew a relationship characterized by financial dependence on someone who has already let you down once before. It is like stepping on a rake, then years later trying to step on the same rake on the off chance it would somehow make the old bruise hurt less. History tends to repeat itself, and you just might end up with another bruise. Why take a chance when you don't have to? I would suggest the exact opposite, i.e. to put a good amount of distance between you and this professors, so as to minimize the chances of making the same mistake (of relying on them and being burned) twice. Good luck!

If I am not mistaken it is part of a professors job to write letters such as the one you requested.  It reflects poorly on the reputation of the school if the professors show little concern for their students future beyond the classroom. I can not imagine many High School students would choose a particular collage if they had information this college would fail them when it came time to securing a future.  If someone feels they do not have time, or would write an unfovorable recommendation, professional ethics would dictate declining. It is reasonable to suggest you make the request in the Professors office as stated by others, providing them with all the information needed, including a date letters must be complete.
It is reasonable to say that it is your responsibility to follow up and make sure the letter was written and submitted.  If the letter is not done in a timely manner, you should have a back up plan. Remember, this is your future and you must be proactive securing what you need to succeed.
Thirty-two years after graduating, I receive letters annually requesting donations to my alma-mater. Upon completion of your degree, you might consider declining donations citing this professors lack of concern for your future. No professor would accept excuses for failing to complete an assignment. No employer would accept excuses for failing to do part of their job. Yes, you should show gratitude for letters of recommendation, but letters from Professors are not mearly favors. Suggesting a letter may have been stolen from a mail box is not an excuse a professor would accept, neither should you.

The question is "What can I do?". You did not really answer it except "you might consider declining donations"?

Not writing a letter of recommendation when you've agreed to write one and you understand the impact it could potentially have on somebody's career is clearly not a great thing to have done - indeed, if you talk to the professor about it in a non-accusatory way (i.e. one that doesn't put him on the defensive), he'll probably feel bad about it.
However, as others have pointed out, the reality of the situation is that you asked somebody potentially busy and perhaps forgetful for a favour that was crucial to you, but probably not that crucial to him. Human nature being what it is, he probably meant to do it, but procrastinated and then forgot about it. It's much easier to forget about things that aren't crucial to you personally, and there's very rarely any malice in it.
What you ought to have done was ask him again politely before each application, making what he needed to do and the deadline extremely clear in each case, and then followed up with him at intervals before the deadline to make sure that he followed through on it. I've always used this method - it works.
Should he automatically have sent in the references without you having to chase him? Sure, maybe, but people are imperfect, and this was something that really mattered to you. Making a huge issue of it years after the fact rather than making sure it didn't happen in the first place is neither sensible nor a useful use of your time. You're much better off chalking it up to experience and doing things differently next time.
See also:
https://en.wikipedia.org/?title=Hanlon%27s_razor

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text:
Is it unfair for a journal to change a decision on an accepted paper if it is later found to be too derivative of the author's previous work?
I edit a journal and we have recently started using similarity checks.  We have a paper that we accepted, but before we published it we found that it is very similar to  previous papers of the author.
I don't know that it is plagiarism, but it only makes incremental progress, and pulls several introductory passages with only minute changes from other papers.  If we had seen this earlier would have editorially rejected it.
The reviewers did not notice the similarity, and it seems not uncommon in the particular area that this paper comes from.
Am I out of line to change the journal's decision on the paper? The paper was submitted a year ago, and has been 'accepted' for 6 months. The average submission to publication time in our field is about 1-2 years.
I don't think I feel right just changing the decision without a 'retraction' level accusation of plagiarism.  Would it be appropriate to at least ask that the introduction be rewritten to remove some of the similarity to previous works?

(1) Are the previous papers from which material is taken actually cited? (2) Would the "only incremental progress" be good enough that you'd still be OK to have this published in your journal, apart from pulling too much stuff from earlier papers? ("Incremental progress" is still progress...)

The results are properly cited. What is not made clear in the paper, but that the similarity check reveals, is that the proofs of the generalizations are mostly the same as the results that they are generalizing.   So I don't call it plagiarism.   Even if the writing were adjusted fixed, I think the progress is insignificant enough that I would not accept the paper.

Based on this I support the answer of @cbeleites.

Summary
IMHO, after the decision to accept (regardless whether it is before actual publication), taking back that acceptance is already a retraction and should thus be subject to the rules for retraction.

Long version

I don't know that it is plagiarism, but it only makes incremental progress, and pulls several introductory passages with only minute changes from other papers. If we had seen this earlier would have editorially rejected it.

As @Allure points out, plagiarism is a reason for retraction, and would be more than enough to correct the wrong decision of acceptance.
The "pulled from other papers" is difficult to judge for me: sometimes, once a good way of introducing a topic found, it can IMHO actually be good not to deviate from it for the sole sake of having new words*. But of course there's a limit to this, and above that it actually is plagiarism and likely also a copyright violation. Then @Allure's answer would apply.
I will assume  here that this boundary is not clearly crossed (according to your description).
While it is fine to never accept a paper that does not have sufficient novelty (i.e. is incremental), after acceptance it is IMHO too late for this.
In German we have a technical term Rechtsfrieden which may be translated as legal certainty. The idea behind that is that even if (here: adminstrative) errors happen, the certainty that decisions are done with and final is important as well. After the decision to accept, taking back that acceptance is IMHO a retraction and should thus happen only in cases that are sufficiently serious for retraction. I'd also call it a retraction then. Otherwise, the "acceptance" would only be a "preliminary acceptance before publication".
We do know that the review and editorial process is far from perfect, so maybe this is only of those papers that slipped in and that maybe shouldn't have but are also not a super-serious mistake.
So I'd say: You've made your bed, now you must lie on it. A mistake happened during the editorial process - that's unfortunate, but IMHO the thing to do now to learn from it and make sure it doesn't happen again - and otherwise move on.

* This convinced me: when writing one of my first papers, my prof told me: this is not a literature class where it's considered nice style to not repeat words. This is science, and the purpose is to communicate unambiguously, and to an audience that are mostly not native English speakers [including ourselves]. Use well-defined terms and easy and clear phrases and stick to them. We want the reader to put their mental work into understanding the topic, not the grammar or vocabulary.

Your answer confirms exactly what I was thinking with extreme clarity. Thank you.  We had decided that is was not academic plagiarism, and would not be retracted, so we could not change our decision.  We did, however ask the authors to re-write the introduction so that there is less a danger of copyright infringement.
The point that once the right introduction is found there seems no need to deviate just to have new words is an interesting take.  Certainly on the scale of a sentence I can agree, but when it gets to half a page, it might be pushing it.

Plagiarism undetected at acceptance is one of the best reasons for rejecting a paper post-acceptance, since it's uncontroversial (it's good enough cause for retraction, and the paper isn't actually published yet). So yes, you are allowed to do this, especially since as an editor of the journal you have carte blanche over what gets published (up to the editor-in-chief overruling you). You are also allowed to request the introduction to be rewritten, if you feel that's more appropriate than retracting the 'accept' decision.
More concerning is how this paper got to acceptance in the first place. Why didn't the publisher do a plagiarism check? How did you not notice it only makes incremental progress? How is the paper still not published six months after acceptance?
If you do decide to reject the paper, it's ideal to tell the publisher to hold off on publishing the paper ASAP. The fact that the paper is still not published after six months suggests the bulk of the typesetting work is already done and something else is causing the holdup (e.g. author is unable to pay the APC), but even in this case, the issues could be fixed any moment, so tell them as soon as possible.

We are a small journal and only recently have been able to do similarity checks.  We weren't able to do them when it was submitted.
The 'six months' is due to a publishing backlog.  If not in all fields, this is quite common for mathematics journals.
I'm not sure why the reviewers didn't notice the incremental progress. The reviews were positive, but not very thorough. I guess I should have tried to get a couple more of them.