Utility Maximization

Consumer choice is based on the idea that people make decisions to maximize their happiness, or utility. The utility maximizing quantity of a good or service can be found when the marginal utility of that product is 0.

This cornerstone of economics can be framed in any form of financial decision, whether it be deciding between spending on movie tickets and going out to eat, or deciding how much to invest in capital, like factories and machinery.

Example:

Those three tennis courts, the four swimming pools, and the porcelain fountain imported from Milan? You own them all. Not to mention a G6 with a hot tub and your own basketball team. So...think of your resources as being, well, infinite. More or less. Utility maximization wouldn't come up much in your life. That is, you’re not too worried about using your pencil after you’ve sharpened it so that it’s only 2 inches long. You just toss it, rather than use another inch.

Utility maximization has to do with decisions consumers make as they spend their limited resources. You get a modest paycheck; you have to figure out how to divide it up. You’ve got rent, food, utilities, entertainment, and all the other stuff you need to live.

So the basic question with regard to utility maximization: how do consumers budget their spending in order to get the most out of it? In other words: how do they maximize utility? Utility maximization has to do with value, or rather, how you allocate precious resources so they produce the most value to you, the consumer. Or, said another way, how consumers get the most satisfaction from the spending of their hard-earned dollars.

Another question: how many gold-plated toilets is Jeff Bezos, founder of Amazon, limited to buy? Answer: he isn’t. The guy has a couple hundred billion dollars in Amazon wealth, so he doesn’t spend a nanosecond worrying about resource allocation. He just buys what he wants. “No, no, no, Mr. Yacht Broker, I’ll take two of ‘em.” But a normal person would probably not take both the pink and the green Buffy and Muffy yachts. In fact, they wouldn’t even be able to afford one. Normal people have constrained budgets and, before they spend their dough, they predict a given level of satisfaction they'll “achieve” from hitting that “Buy now!” button. What they have to spend is essentially a kind of mathematical constraint on their happiness, or utility, or ability to make their life better. So everything in their mindset begins from their financial foundation, i.e. a “budget.”

You're an Average Joe liberal arts major. Your big tradeoff choices might be more about buying ramen noodles in bulk or getting the soft toilet paper. (Hint: buy the Ramen. You can always borrow toilet paper from the Burger King bathroom.) This dynamic is called a budget constraint.

Utility maximization is all about budget choices. The goal of utility maximization is get the most total value from the money you have available to spend. Going back to the bulk ramen...you have $50. It's your last $50 and it has to last you nine days until your next paycheck comes. Costco, the discount retailer, has super-bulk boxes of ramen on sale. The cost for one year’s worth of noodles? $50. Which is great...but for the fact that you will be evicted in an hour, and the cost to remain in your hovel under the freeway for 9 more days happens to be exactly $50.

So you have a tradeoff here. You can either eat, or you can be sheltered, but you can’t do both. So in theory, there should be a tradeoff you could make, where maybe you share a cardboard box for $25 for 9 days with someone, and spend the remaining $25 on noodles that will get you through until you can collect your next paycheck, as you rue the day you committed to being a liberal arts major. Because economists are economists, they have a bunch of mathematical formulas to optimize the budget allocation of your precious dollars. The basic notion behind this math revolves around the idea that consumers will allocate their money so that they get the most marginal utility for each dollar they spend.

Okay, last concept for understanding utility maximization: marginal utility. Marginal utility is the amount of extra use you get out of buying more of something. Like…you need some ramen to keep you alive. But you don’t need 40 pounds of it to keep you alive for 9 days. A storage locker full of ramen won't do you much good; it would just sit around, doing nothing. One pair of pants is good for keeping your legs warm and making sure you don't get arrested. But 1,000 pairs of pants is just wasteful. There's not much marginal utility being gained from that thousandth pair of Dockers.

So utility maximization involves trying to get the most value out of limited resources, such that the n+1th unit then begins to decline dramatically in value. Like…if you need 2,000 calories a day to basically maintain your current weight, and one packet of ramen is 500 calories, then if you need to survive 9 days, you’ll want 4 packets a day for 9 days, or 36 packets to just keep you alive until your next payday. At that point, you hope you can afford to make a change in your life and lifestyle. But for now, you realize that you would probably die, or at least suffer greatly, if you went with no ramen for all 9 days, and just tried to survive on water. You would gain great utility from having at least one packet a day for 9 days, but you’d realize that you’d have lost so much weight in living on 500 calories a day that the storage locker of 1,000 Dockers would have almost no pants that fit you anymore. You would continue to gain meaningful marginal value from the 2nd and 3rd packets of ramen per day, getting you to 1,500 calories a day, such that you might only lose a few pounds over the course of 9 days, until you get to that golden paycheck. After 4 packets a day, the value of those ramen noodles begins to decline massively. Or, said another way, their marginal utility approaches zero.

This set of calculations mirrors the marginal utility value model, with the goal of getting the most marginal utility out of each dollar. Or the most ramen out of each dollar, which is…actually quite a bit of ramen.

Related or Semi-related Video

Econ: What is Utility Maximization?4 Views

00:00

And finance Allah Shmoop What is utility maximization All right

00:09

Those three tennis courts the four swimming pools and the

00:12

porcelain fountain imported from Milan You own them all Not

00:16

to mention a G six with a hot tub and

00:20

your own basketball team So think of your resource is

00:23

as being well infinite Mohr less so Utility maximization wouldn't

00:29

come up much in your life That is You're not

00:32

too worried about using your pencil after you sharpen it

00:35

so that it's only two inches long before you throw

00:37

it out you just toss it rather than use another

00:40

inch Well utility maximization has to do with decisions consumers

00:44

make as they spend Their limited resource is all right

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now you're this guy You get a modest paycheck You

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have to figure out how to divide it up to

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survive You've got rent food utilities entertainment and all the

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other stuff you need Thio live So the basic question

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with regard to utility maximization for you Well how do

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consumers budget they're spending in order to get the most

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out of it In other words how do they maximize

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utility Or how do you do this Utility maximization has

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to do with value Or rather how you allocate precious

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resource is AII Cash So it produces the most value

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to you the consumer Or set another way How do

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consumers get the most satisfaction from spending their hard earned

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dollars Well question How many gold plated toilets is Jeff

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Bezos founder of Amazon Limited to buy Answer He isn't

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limited by budget He is however limited by the happiness

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Each additional gold plated toilet gets him Well the guy

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has couple hundred billion dollars That's with a B in

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Amazon stock wealth so he doesn't spend a nanosecond worrying

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about resource allocation He just buys whatever he wants No

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no no Mr Yacht broker I'll take two of them

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well but a normal person would probably not take both

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the pink and the green Buffy and Muffy yachts In

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fact they wouldn't even be able to afford one yacht

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of shame Normal people have constrained budgets and before they

02:10

spend their dough they predicted given level of satisfaction they

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quote achieve unquote from hitting that by now button What

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they have to spend is essentially a kind of mathematical

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constraint on there Happiness or utility or ability to make

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their life better What they have to spend is a

02:28

constraint on their budget They need to make tradeoffs among

02:32

the items they need to buy based on the happiness

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each additional unit of whatever gets them So now back

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to the average Joe liberal arts major your big tradeoff

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choices might be more about buying ramen noodles in bulk

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or getting the soft toilet paper hint by the ramen

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You can always borrow toilet paper from the Burger King

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bathroom or you know there's a newspaper laying around somewhere

02:58

This dynamic is called a budget constraint beautifully graphically illustrated

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here for your viewing pleasure Yeah Check this out And

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here's a graph of Jeff Bezos Budget constraint Yeah not

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much constraint you know financially yet Well utility maximization is

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all about these budget choices The goal of utility maximization

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is to get the most value from the money you

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have available to spend As an example We're making tradeoffs

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between toilet paper and Rahman Here we have a budget

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that shows our trade offs of the two Well here's

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an indifference curve which measures the happiness we get from

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each and where the slope of the indifference curve is

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tangent to the budget constraint That's where we have the

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maximum utility IAEA happiness within our budget constraint Getting all

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this all right Now let's talk about another trade off

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You have fifty boxes your last fifty bucks and it

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has to last you nine days until your next liberal

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arts style paycheck comes Costco the discount retailer has super

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bulk boxes of Rahman on sale in a cost for

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one month worth of noodles Well fifty bucks which is

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grey but for the fact that you will be evicted

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in an hour And the cost to remain in your

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hovel into the freeway for nine more days happens to

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be exactly fifty dollars Well that's the amount You pay

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the head bum to tell the other bums not to

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beat you senseless at night and steal your liver while

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you're sleeping on the freeway there So you have a

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trade off here You can either eat or you Khun

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B Sheltered but you can't do both So in theory

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there should be a tradeoff you could make where fell

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Maybe you share a cardboard box with another bum for

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twenty five dollars for nine days and spend the remaining

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twenty five dollars on the well two weeks worth of

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noodles that will get you through until you can collect

04:44

your next paycheck As you rue the day you know

04:47

that you did that whole liberal arts major thing Well

04:49

because economists are economists they have a bunch of mathematical

04:52

formulas to optimize the budget allocation of your precious dollars

04:56

The basic notion behind this math revolves around the idea

04:58

that consumers will allocate their money so that they get

05:01

the most marginal utility for each dollar they spend Right

05:06

Last dollar it's going to go in the best place

05:08

to them Okay Last concept for understanding utility maximization here

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for marginal utility is the amount of extra use you

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get out of buying mohr of something like you need

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some rahmon to keep you alive But you don't need

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like forty pounds of it to keep you alive For

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just nine days A storage locker full of Rahman will

05:27

not do much good for you It would just sit

05:29

around doing nothing right What One pair of pants is

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good for keeping your legs warm and making sure you

05:35

don't get it You know arrested you know been there

05:37

done that But a thousand para pants Well just wasteful

05:40

There's not much marginal utility being gained from that thousand

05:44

pair of you know khaki Dockers So utility maximization involves

05:49

trying to get the most value Out of limited resource

05:51

is such that the N plus one unit then begins

05:55

to decline dramatically in value art Example Like if you

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need two thousand calories a day to basically maintain your

06:02

current weight and one packet of Rahm and his five

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hundred calories Well then if you need to survive nine

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days while you'll want four packets a day for nine

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days or thirty six packets to just keep you alive

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until your next paycheck after nine days At that point

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you hope you can afford to make a change in

06:18

your life and lifestyle But for now you realize that

06:21

you would probably die or at least suffer greatly If

06:23

you went with no Roman for all nine days and

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just tried to survive on water you would gain great

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utility from having at least one packet today for nine

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days But you'd realize that you have lost so much

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weight in living on five hundred calories a day That

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the storage locker of a thousand docker pants would have

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almost no hands that fit you anymore Yeah you would

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continue to gain meaningful marginal value from that second and

06:48

third packets of Rahman a day getting you to a

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fifteen hundred calories a day Such that Well you might

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only lose a few pounds over the course of those

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nine days until you got that golden paycheck That'd be

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just fine And after for four packet today well the

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value of those Rahman noodles begins to decline massively or

07:05

set another way there Marginal utility than approaches Zero Well

07:09

this set of calculations mirrors the marginal utility value model

07:13

with the goal of getting the most marginal utility out

07:16

of each dollar or the most rum and out of

07:19

the dollar which is actually quite a bit of Roman

07:24

and

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