Dollar Auction

  

Categories: Econ, International, Banking

Economists make a lot of assumptions when they make their models. One of the biggest and most common assumptions they make is that people are rational. We’d like to think that people, capable of building cities and atomic bombs...of building a global civilization...and of destroying it in under a minute...are rational creatures.

The dollar auction runs where two people are bidding on a dollar. The winner will get the dollar, and the loser will have to pay up whatever their last bid was. So players aren’t only trying to win, they’re also trying to minimize what they might lose. Once the bidding goes above $1, it makes sense to keep bidding. For instance, if your last bid was $0.95, and the other player’s bid was $1, then it would make sense for you to bid $1.01 to avoid losing $0.95. If this kept going, with infinite bidding, then each player would bid one cent through eternity.

Like the Prisoner’s Dilemma, this game shows that the rational choice doesn’t always lead to what appears to be the most rational outcome, especially when people aren’t working together, and instead are working in their own self-interest. For instance, it’s not rational to bid more than $1 to earn $1, but each player in the dollar auction is incentivized to keep bidding one cent more when it passes the $1 mark. If they worked together and said “okay, this is silly, let’s stop” it would lead to a more “rational outcome,” but how would they decide who's the last person to bid, i.e. the winner?

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Finance: What are Treasury Bills?15 Views

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finance a la shmoop. what are Treasury bills? well the US government is a

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financial pig. it borrows money all the time [pig crosses screen]

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senators. tea bills are just one way in which the government raises cash for

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itself to you know buy things. the deal works like this.

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investors write a check to the US government taking their hard-earned cash

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and giving it to Uncle Sam who in return gives them a piece of paper promising to

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pay them back in a short ish period of time .while tea bills are like that

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they're typically short in duration and they sell at a discount to par like a

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zero coupon bond .meaning that an investor might pay nine hundred eighty [zero coupon bonds explained]

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two dollars for a thousand dollar par bond which comes due in six months. the

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investor for loaning the government her nine hundred eighty two dollars in cash

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for six months gets paid eighteen dollars in rent on that money. there are

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no interest payments made along the way as there would be in a traditional bond

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investment which typically pays interest twice a year. in this case the investor

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is just buying a grand at a discount. simple .and note that in this case the

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investment return is eighteen bucks on a grand for six months. that implies an

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testing you here a little bit just seeing if you're awake. well if an

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investor makes eighteen bucks in six months which is half a year if you

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doubled the six months to be twelve months or a full year well you could

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also double the eighteen bucks to be thirty-six bucks and yeah that's it.

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notionally had the government rented that grand for a year it would have paid

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thirty-six dollars for the privilege or three point six percent interest

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annualized. thirty-six bucks over a grand. that's how we got there but it's not

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quite accurate why? because the investor didn't put in a full grand ,they will

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have put in less. well in this example they invested nine hundred eighty two

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dollars and they got back eighteen bucks for six months of doing a whole lot of [piggy bank called "U.S gov."]

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nothing. watching the clock and hoping the US

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government wouldn't go bankrupt during that time period. so the interest rate of

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return to the investor? well you take 18 bucks and divide it by 982 and you get

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more like three point six six percent or so .small change but on big numbers that

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adds up and now with investor money the government is free to do all its pork

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spending. maybe a nice new sty for the Speaker of the House. what do you think? [pig walks on back legs through a store carrying a basket]

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