Game Development Reference
In-Depth Information
“Here,� I said. “I don't know how much value you put on five minutes of
your
time,
but five minutes of
my
time is worth more than the price of a can of peas.�
There was a silent moment during which she displayed a thoroughly bewil-
dered look (which was worth more to me than a can of peas). Collecting herself
(but still probably uncomprehending that her time could possibly be worth more
than 20 cents), she managed a brief nod to the cashier who, by this point, was
beaming worshipfully at me like I was the grocery store equivalent of Charles
Bronson in
Death Wish
. The price check was cancelled, the lady paid, and I left the
store 30 seconds later.
What is the point of my reflective anecdote? While the
value
of the can of
peas was the same 78 cents for both of us, the lady obviously had a higher
utility
for
that 78 cents than did I. And the
utility
was the important factor in making the
decision… not the
value.
U
TILITY VS
. R
ISK
As we have discussed thus far, goals and tools can often be expressed in terms of
utility. This may or may not equate to their stated value. Earlier in this chapter we
also discussed the act of taking risks (or not taking them) in terms of utility. This
becomes useful to us when we combine and compare the utility of the risk with the
utility of the outcome. When we do this, we arrive at an expression that may yield
an inequality of varying magnitude. It is this inequality that allows us to determine
whether or not a risky activity is “worth it.�
For purposes of keeping to a simple example, it would be best if we stay within
the realm of a single, measurable unit. For now, we can construct an example that
uses money as the manner of measurement for both the risk and the reward. To
that end, let's begin with a scenario that is likely familiar to many of us.
Warranties and Risk
Imagine purchasing a computer for $1,400. With tiresome predictability, the sales-
person offers you a warranty that offers free repair for your computer for a year at
a cost of $300. (Yeah, I know… that's a little steep.) The question, naturally, is
whether or not you should purchase the warranty.
Obviously, the decision as to whether or not to purchase a warranty is based
largely on our expectation about whether the computer will need repair during the
warranty period. (Repairs normally cost $200.) We are also going to consider
the possibility that the machine could completely implode beyond repair and need
to be replaced.
