<p>&quot;From my understanding,&quot; treatment is simultaneous&quot; is that all countries passed a law at the same time, is this correct?&quot;</p>
<p>Yes.</p>
<p>And what is multiple treatment events can happen in the same unit ?</p>
<p>The same individual can be treated several times. i.e. suppose treatment is a binary variable for &quot;the minimum wage increased&quot;. A region may have several increases in the minimum wage over the course of a data set.</p>

CC BY-SA 4.0
2021-09-16T21:04:34.113Z
Thanks @Micheal, but it is not totally clear to me about the "same individual can be treated several times". So, in each time the minimum wage increases, what is the movement of the binary variable ?
Phil Nguyen
CC BY-SA 4.0
2021-09-16T22:22:52.370Z
@Louise I agree with you that "multiple treatment events" is a bit obscure without more information. For example, multiple treatments could be a unit experiencing, say, two *sequential* treatments, meaning they happen one after another. For example, the policy variable could represent different levels of intensity. On the other hand, a multi-treated unit could also mean a unit experiences a treatment intermittently; this is more characteristic of the 'on' and 'off' exposure pattern you referenced, such as when policies sunrise and sunset *repeatedly* over time.
Thomas Bilach
CC BY-SA 4.0
2021-09-16T22:25:06.897Z
Agreed! I got what you mean, thanks @Thomas
Phil Nguyen
CC BY-SA 4.0
2021-09-16T22:26:53.607Z
"two sequential treatments, meaning they happen one after another. For example, the policy variable could represent different levels of intensity", and at that time, the treatment variable is no longer a binary one, I deem.
Phil Nguyen
CC BY-SA 4.0
2021-09-16T22:42:12.650Z
@Louise It could be binary. In other words, it could be a discretized measure (e.g., low, medium, high, etc.) representing the different exposures. Software will usually 'dummy out' the different levels for you. So, technically, they are binary variables representing the different levels of treatment. Does that make sense?
Thomas Bilach
CC BY-SA 4.0
2021-09-16T22:45:14.803Z
@Thomas, ah I see, different binary for different levels. I got it. Thanks
Phil Nguyen
CC BY-SA 4.0
2021-09-16T22:54:56.090Z
@Louise By the way, a continuous measure can replace the binary treatment indicator. If you have a continuous treatment variable, then include it! I'm just letting you know that the model can also handle more than one 'discrete' treatment variable.
Thomas Bilach
CC BY-SA 4.0
2021-09-16T16:27:49.660Z
2021-09-16T16:27:49.660Z
Michael Gmeiner
<p><a href="https://www.mendeley.com/catalogue/b1e55330-f605-363c-b07f-3ab67325e929/" rel="nofollow noreferrer">Borusyak (2021)</a> writes the following:</p>
<blockquote>
<p>We further discuss the implications of our results when <strong>treatment is simultaneous</strong> rather than staggered, when <strong>it can switch on and off</strong>, and when <strong>multiple treatment events can happen in the same unit</strong>.</p>
</blockquote>
<p>There are three treatment styles in the above sentence. From my understanding, &quot;when it can switch on and off&quot; means that the laws can be implemented and removed after a period in the same country. But I don't understand the definition of the other two treatment styles: <strong>treatment is simultaneous</strong> and <strong>multiple treatment events can happen in the same unit</strong>.</p>
<p>From my understanding, &quot;treatment is simultaneous&quot; means that all countries passed a law at the same time. Is this correct? And what is <strong>multiple treatment events can happen in the same unit</strong>?</p>

<econometrics><definition><treatment-effect>
Asking for the definition of various types of treatment?
Phil Nguyen
# Asking for the definition of various types of treatment?

(Asked by: username_0 on 2021-09-16)

[Borusyak (2021)](https://www.mendeley.com/catalogue/b1e55330-f605-363c-b07f-3ab67325e929/) writes the following:

> We further discuss the implications of our results when **treatment is simultaneous** rather than staggered, when **it can switch on and off**, and when **multiple treatment events can happen in the same unit**.

There are three treatment styles in the above sentence. From my understanding, "when it can switch on and off" means that the laws can be implemented and removed after a period in the same country. But I don't understand the definition of the other two treatment styles: **treatment is simultaneous** and **multiple treatment events can happen in the same unit**.

From my understanding, "treatment is simultaneous" means that all countries passed a law at the same time. Is this correct? And what is **multiple treatment events can happen in the same unit**?

**Tags:** econometrics, definition, treatment-effect

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## 1 answers

### Answer by username_1 on 2021-09-16. Score: 2 | Accepted answer

"From my understanding," treatment is simultaneous" is that all countries passed a law at the same time, is this correct?"

Yes.

And what is multiple treatment events can happen in the same unit ?

The same individual can be treated several times. i.e. suppose treatment is a binary variable for "the minimum wage increased". A region may have several increases in the minimum wage over the course of a data set.

> **Comments:**
> **username_0**: Thanks @Micheal, but it is not totally clear to me about the "same individual can be treated several times". So, in each time the minimum wage increases, what is the movement of the binary variable ?  
> **username_2**: @Louise I agree with you that "multiple treatment events" is a bit obscure without more information. For example, multiple treatments could be a unit experiencing, say, two *sequential* treatments, meaning they happen one after another. For example, the policy variable could represent different levels of intensity. On the other hand, a multi-treated unit could also mean a unit experiences a treatment intermittently; this is more characteristic of the 'on' and 'off' exposure pattern you referenced, such as when policies sunrise and sunset *repeatedly* over time.  
> **username_0**: Agreed! I got what you mean, thanks @Thomas  
> **username_0**: "two sequential treatments, meaning they happen one after another. For example, the policy variable could represent different levels of intensity", and at that time, the treatment variable is no longer a binary one, I deem.  
> **username_2**: @Louise It could be binary. In other words, it could be a discretized measure (e.g., low, medium, high, etc.) representing the different exposures. Software will usually 'dummy out' the different levels for you. So, technically, they are binary variables representing the different levels of treatment. Does that make sense?  
> **username_0**: @Thomas, ah I see, different binary for different levels. I got it. Thanks  
> **username_2**: @Louise By the way, a continuous measure can replace the binary treatment indicator. If you have a continuous treatment variable, then include it! I'm just letting you know that the model can also handle more than one 'discrete' treatment variable.  

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