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<h2>Utility of money (Assignment 3), Psych. 153/600, Fall 2008</h2>

Enter your full upenn email address (ending in .upenn.edu):
<br /><input type="text" size="70" id="aemail" name="aemail" />
<p>Enter your name:
<br /><input type="text" size="70" name="aname" />
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<p>This is about the utility of annual income in retirement.
The idea is to decide how to allocate your pension fund between
safe and risky investments.  Suppose that, when you retire, you
will get $25,000/year in social security (in today's dollars).
The questions here refer to what you get in addition to that,
from your own saving.  The range of possibilities is from $0 to
$200,000 per year.</p>

<p>We shall assume that the utility of $0 is 0 and the utility of
$200,000 is 100.  You will use 3 methods to get your utility
function for the intermediate intervals.</p>
<hr />

<p>The first method is <b>direct ratings</b>.  Remembering that the
utility of $0 is 0 and the utility of $200,000 is 100,
what is the utility of $100,000?  This is a question about judgment,
not calculation.  The utility of $100,000 might be more than 50 or less than 50.
<br /><input type="text" id="direct20" name="direct20" size="4" /></p>

<p>Now rate the utility of $50,000 and $150,000.
<br /><input type="text" id="direct10" name="direct10" size="4" /> for $50,000.
<br /><input type="text" id="direct30" name="direct30" size="4" /> for $150,000.</p>
<p><input type="button"
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<hr />

<p>The next method you use is the <b>standard gamble</b>.  What
question should you ask yourself to get each of the three ratings you
just did, so that the answer (without any change) would be the utility of $100,000?  Select
the question and answer it.  (Try not to think about your earlier
answers, and answer in percent without adding another percent sign.)</p>

<p><label><input type="radio" class="radio" name="1" value="1" />
At what probability P would I be indifferent between $200,000 with probability P
(and 0 with probability 1-P) and $100,000 for sure?</label>
<br /><label> <input type="radio" class="radio" name="1" value="2" />
At what probability P would I be indifferent between $200,000 with
probability 1-P (and $0 with probability P) and $100,000 for
sure?</label>
<br /><label> <input type="radio" class="radio" name="1" value="3" />
At what probability P would P times $200,000 equal $100,000?</label></p>

<p>Answer to the question you asked yourself:
<br /><input type="text" id="sg50" name="sg50" size="4" />%</p>

<p>Now chose the corresponding question and provide answer for
$150,000, and then just give the answer for $50,000.
<br /><label> <input type="radio" class="radio" name="2" value="1" />
At what probability P would I be indifferent between $200,000 with
probability P (and 0 with probability 1-P) and $150,000 for
sure?</label>
<br /><label> <input type="radio" class="radio" name="2" value="2" />
At what probability P would I be indifferent between $200,000 with
probability 1-P (and $0 with probability P) and $150,000 for
sure?</label>
<br /><label> <input type="radio" class="radio" name="2" value="3" />
At what probability P would P times $200,000 equal $150,000?</label></p>

<p><input type="text" id="sg75" name="sg75" size="4" />% for $150,000.
<br /><input type="text" id="sg25" name="sg25" size="4" />% for $50,000.</p>

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  <text x="230" y="470" fill="black">$100</text> 
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<hr />

<p>The third method you use is another way to do direct rating,
namely, <b>bisecting</b> intervals.  What salary would have a
utility of 50?  That is, in terms of what matters to you, the
difference between this level and $0 should be the same as the
difference between this level and $200,000.
<br />$<input type="text" id="bisect50" name="bisect50" size="4" />,000</p>

<p>Now answer this question in the same way, by dividing each half
in half, for utilities of 75 and 25:
<br />$<input type="text" id="bisect75" name="bisect75" size="4" />,000 for 75.
<br />$<input type="text" id="bisect25" name="bisect25" size="4" />,000 for 25.</p>

<p><input type="button"
   value="Click to see utility function in red, below." onclick="set3();" /></p>

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<hr />

<p>If your utilities measured by gambles and those measured by
bisection (third method) are different, how?  Consider only
the utility of $100,000 (relative to $0 and $200,000).</p>

<p><label> <input type="radio" class="radio" name="3" value="1" />
Gambles are more concave.</label>
<br /><label> <input type="radio" class="radio" name="3" value="2" />
Gambles are more convex (less concave).</label>
<br /><label> <input type="radio" class="radio" name="3" value="3" />
Equal.</label></p>

<p>Which of the following would <b>explain greater concavity</b> for gambles
than for bisection?  Answer yes or no for each.
<br />Declining marginal utility would lead people to overvalue the outcome that
was certain.
<br /><label><input type="radio" class="radio" name="4" value="1" />Yes</label>&nbsp;
<label><input type="radio" class="radio" name="4" value="2" />No</label>
<br />The certainty effect would lead people to overvalue the outcome that
was certain.
<br /><label><input type="radio" class="radio" name="5" value="1" />Yes</label>&nbsp;
<label><input type="radio" class="radio" name="5" value="2" />No</label>
<br />People tend to be risk seeking in the domain of losses.
<br /><label><input type="radio" class="radio" name="6" value="1" />Yes</label>&nbsp;
<label><input type="radio" class="radio" name="6" value="2" />No</label>
<br />If people adopt the certain outcome (e.g., $100,000) as a
reference point, then loss aversion would make them more risk averse.
<br /><label><input type="radio" class="radio" name="7" value="1" />Yes</label>&nbsp;
<label><input type="radio" class="radio" name="7" value="2" />No</label>
</p>

<hr />

<p>Portfolios with the highest average returns also tend to have the 
highest chance of short-term losses. The table provides
the average dollar return of four hypothetical investments of
$100,000 and the possibility of losing some money (coming out below
$100,000) over a one-year holding period.  Figures are adjusted for
inflation.  Note that you could get more than the expected value.
Which would you choose?  (Note: This example is based on
one used by TIAA-CREF.)
<br /><label> <input type="radio" class="radio" name="8" value="1" />
Expected value after 1 year: $100,000.<br />Chance of losing
money at the end of 1 year: 0%</label> (In other words, this has no risk.)
<br /><label> <input type="radio" class="radio" name="8" value="2" />
Expected value after 1 year: $105,000.<br />Chance of losing
as much as $5,000 at the end of 1 year: 15%</label>
<br /><label> <input type="radio" class="radio" name="8" value="3" />
Expected value after 1 year: $110,000.<br />Chance of losing
as much as $10,000 at the end of 1 year: 30%</label>
<br /><label> <input type="radio" class="radio" name="8" value="4" />
Expected value after 1 year: $115,000.<br />Chance of losing
as much as $15,000 at the end of 1 year: 45%</label>
<br /><label> <input type="radio" class="radio" name="8" value="5" />
Expected value after 1 year: $120,000.<br />Chance of losing
as much as $20,000 at the end of 1 year: 60%</label></p>


<p>Why might the last question yield answers that, if taken at
face value, would fail to maximize utility? (Answer yes or no to each.)
<br />Loss aversion leads to more risk aversion than would be
inferred from the utility function for income at retirement.
<br /><label><input type="radio" class="radio" name="9" value="1" />Yes</label>&nbsp;
<label><input type="radio" class="radio" name="9" value="2" />No</label>
<br />A concave utility function for income at retirement leads to excessive risk aversion.
<br /><label><input type="radio" class="radio" name="10" value="1" />Yes</label>&nbsp;
<label><input type="radio" class="radio" name="10" value="2" />No</label>
<br />Decision utility could differ from experienced (true) utility.
<br /><label><input type="radio" class="radio" name="11" value="1" />Yes</label>&nbsp;
<label><input type="radio" class="radio" name="11" value="2" />No</label>
<br />The value function for income at retirement is convex for losses.
<br /><label><input type="radio" class="radio" name="12" value="1" />Yes</label>&nbsp;
<label><input type="radio" class="radio" name="12" value="2" />No</label></p>

<!--
<p>If your utilities measures by direct rating and those measured by
bisection are different, how?  Consider only the utility of $100,000
(relative to $0 and $200,000).</p>

<p><label> <input type="radio" class="radio" name="6" value="1" />
Bisection is more concave.</label>
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Bisection is more convex (less concave).</label>
<br /><label> <input type="radio" class="radio" name="6" value="3" />
Equal.</label></p>
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