<blockquote>
  <ol>
  <li>What do $U_i&gt;0$ and $U_{ii}&lt;0$ mean? Is this the British way of denoting prime and double prime?</li>
  </ol>
</blockquote>

<p>Seems like it. It just indicates the all the first and second derivatives that exsist in this context.</p>

<blockquote>
  <ol start="2">
  <li>Assume utility is derived from three variables; the two indicated by the author and a third, say... happiness ($H$). How would this be expressed? I have only seen utility expressed as a function of two factors and I'm curious how more than two are dealt with.</li>
  </ol>
</blockquote>

<p>The utility function is now $U(C,L,H)$. we still end up with first and second condtions being $U_i&gt;0$ and $U_{ii}&lt;0$ except now $i=C,L,H$.</p>

<p>Hope this helps.</p>

CC BY-SA 3.0
2017-03-31T19:31:53.090Z
2017-03-31T22:28:26.160Z
2017-03-31T22:28:26.160Z
EconJohn
<p>Here is an excerpt from a journal article:</p>

<p>"A solicitor's input decision on a given case can be thought of as a labour supply  decision, with the movement towards standard fees altering the budget constraint  the solicitor faces (Gray et al., 1996). Start with fee-for-service remuneration.  Assume that solicitors derive utility from consumption $(C$) and leisure $(L)$,  $U(C, L), U_i &gt; 0, U_i{_i} &lt; 0, i = C, L$."</p>

<p>Here are my two questions: 1. What do $U_i&gt;0$ and $U_i{_i}&lt;0$ mean? Is this the British way of denoting prime and double prime? 2. Assume utility is derived from three variables; the two indicated by the author and a third, say... happiness ($H$). How would this be expressed? I have only seen utility expressed as a function of two factors and I'm curious how more than two are dealt with.  </p>

<microeconomics>
Utility Function
c4sadler
# Utility Function

(Asked by: username_0 on 2017-03-31)

Here is an excerpt from a journal article:

"A solicitor's input decision on a given case can be thought of as a labour supply decision, with the movement towards standard fees altering the budget constraint the solicitor faces (Gray et al., 1996). Start with fee-for-service remuneration. Assume that solicitors derive utility from consumption $(C$) and leisure $(L)$, $U(C, L), U\_i > 0, U\_i{\_i} < 0, i = C, L$."

Here are my two questions: 1. What do $U\_i>0$ and $U\_i{\_i}<0$ mean? Is this the British way of denoting prime and double prime? 2. Assume utility is derived from three variables; the two indicated by the author and a third, say... happiness ($H$). How would this be expressed? I have only seen utility expressed as a function of two factors and I'm curious how more than two are dealt with.

**Tags:** microeconomics

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## 1 answers

### Answer by username_1 on 2017-03-31. Score: 2 | Accepted answer

> 1. What do $U\_i>0$ and $U\_{ii}<0$ mean? Is this the British way of denoting prime and double prime?

Seems like it. It just indicates the all the first and second derivatives that exsist in this context.

> 2. Assume utility is derived from three variables; the two indicated by the author and a third, say... happiness ($H$). How would this be expressed? I have only seen utility expressed as a function of two factors and I'm curious how more than two are dealt with.

The utility function is now $U(C,L,H)$. we still end up with first and second condtions being $U\_i>0$ and $U\_{ii}<0$ except now $i=C,L,H$.

Hope this helps.


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