Roll's Critique

Categories: Financial Theory

If you’re a pro investor (or just watch Cramer endlessly), you’ve no doubt heard of the capital asset pricing model (CAPM). CAPM is a widely used strategy by investors, who abide by its advice to diversify, diversify, diversify. Don’t put all those eggs in one basket.

Economist Richard Roll (brother of Tootsie) believed that you can’t actually create a diversified market portfolio, at least not without investing in every investment in every market...all commodities, rare items...anything and everything with value that’s being sold as an investment.

Anything else is just trying to set up a proxy version of a balanced, diversified portfolio, even if it follows a market index. For instance, CAPM relies on the S&P 500 as a base for overall market return. Roll’s says it's very narrow-minded to assume that any one market, index, or what-have-you could accurately approximate the entire market.

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Finance: What is a WACC Model?18 Views

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Finance allah shmoop What is a lack model That's whack

00:07

Yeah it is people We had to go there once

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okay we're done Quack stands for weighted average cost of

00:15

capital and whoa yeah that's a mouthful heavy term but

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the concept's pretty simple All right Well let's say you

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run the famed charcoal smoker producer grills grills grills or

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grilles Cubed is matthew people like you said and you

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want to buy We've got gas The finest purveyor of

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propane grills on the market which will help grills Grilled

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grills rule the outdoor barbecue market no matter what their

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customers Fuel of choices Well you need to borrow a

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ton of money to buy out your competitors A billion

00:50

dollars worth of borrow in fact it's so much dough

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that you have to borrow it from three different places

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Well the money you're borrowing is the capital You need

01:00

to buy your target We've got gas That's your target

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Okay capital c and wacker at least one Well the

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bank demands that the bank comes first in priority Should

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things you know go awry and you go the b

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word Yeah Bankruptcy We we don't like to say that

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too loudly Run banks Okay well the bank will loan

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you two hundred million dollars and we'll charge you five

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percent interest on that money That five percent is your

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cost of capital from that bank lender for funding round

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number two while you turned a sweet and beatrix who

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in addition to being a killer grill meister in her

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own right Well she also happens to be loaded So

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anti b agrees to loan you the second traunch of

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money and we'll come in second in priority behind the

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bank in collecting her dough Should you know the b

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word happened She'll own you seven hundred million at seven

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percent interest Great So now you only have to raise

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your last hundred million box and it has to come

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third in the priority stack up of collecting Should things

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go you know awry With no other options you hit

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up tony mafia ony the shadiest loan shark on either

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side of the mason dixon So you pay your respects

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you know just the glove with tongue and things get

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a little weird But somehow at the end of the

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day you walk away from tony's headquarters with a wallet

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full of cash as your stomach is full of non

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amalfi onis sunday raghu what That last hundred million box

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comes with a very high interest price Twelve percent So

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when the tony notes ironically that quack is the same

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noise that baseball bats make when they hit knees when

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will you pay attention And you do the math keenly

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aware that the waiting's here are very different looks like

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this and that the huge middle traunch of seven hundred

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mil it's seven percent has the biggest effect on your

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cost of capital because well it's a big fat seventy

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percent of the total amount you're borrowing Well the first

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two hundred mill is cheap at five percent and it

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costs you ten million bucks here to rent that money

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The second trunk of seven hundred million is kind of

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sort of mad sheepish at seven percent and it costs

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forty nine mil a year to rent and that last

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traunch of one hundred mil is super expensive for what

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you're getting costing you twelve million a year to rent

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So you add up the capital rental costs of ten

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plus forty nine plus twelve and you get seventy one

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million box to rent a billion dollars for this transaction

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that seventy one mil to rent a bill and pay

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that runs So what is your whack or weighted average

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cost of capital Well seventy one million over a billion

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or seven point one Percent The black models always percentage

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Some companies will use their stock to buy a competitor

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er rather than using cash But that's not always the

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case and calculating the cost of equity is way more

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complex and involves a lot more smoke and or mirrors

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So we're just doing debt here people and there you

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have it Whack in a nutshell But you know what's

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not whack shmoop snu finance themed hip hop album on

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sale soon coming soon to a itunes thinking you're you 00:04:04.93 --> [endTime] yeah we'll eat your heart out there hamilton

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