eric falkenstein. there are a few areas where we see a risk premium insurance against accidents...
TRANSCRIPT
Eric Falkenstein
There are a few areas where we see a risk premiumInsurance against accidentsShort end of the yield curve
On average, no risk premiumNegative risk premium to high riskPeople seem to be gambling, not investing, in
practice, with the same expected return to gambling
Say utility is relative
Y riskier than X in standard approachY and X same risk in relative senseRisk is unnecessary: choose ½(X+Y)Like idiosyncratic risk, unnecessary risk
unpriced
U x U x x
X Y avg X-avg Y-avg
State 1 0 -10 -5 5 -5
State 2 20 30 25 -5 5
Avg 10 10 10 0 0
Easterlin ParadoxBenchmarking, tracking error as riskNot a new idea
Adam Smith, Karl Marx, Thorsten Veblen, Max Weber, all focused on status (didn’t formalize)
Pesendorfer (1995) and Rayo and Becker (2006) modeled status orientation formally
Two assets, a risky security and a risk-free security, with returns RE and Rf
Where (risk free return is certain)There are two identical agents, i and –i, who
have wealth in period 0 of k, and spends money, , on the two assets
No consumption. In the next period, agent i’s wealth is thus
i iE fk a a³ +
( ) ( )2~ , , ~ ,0E ffR N R N Rms
1 i ii E f E Ew k R R
Utility is relativeMax utility subject to budget constraint
Substituting for , because the budget constraint holds with equality.
( ) ( )1 1 1 1
, E
2
. .
i iE f
i iE f
i i i i
k
aw w Var w w
st
Maxa a
a a
- -
³ +
- - -
( ) ( ) ( )2 2
+ 2ff
iE
i i i i i iE E E E E Ek R k R
aMaxa
m ms
a a a a a a- - -- -- - - -
( ) { }1 1 1 1expi i i i iU w w a w wæ ö÷ç ÷ç ÷ç- -è ø- = - - -
i if Eka a= -
Taking the first order condition, we have
Since each agent is identical, in equilibrium each agent holds the same amount
SoOr Which means, the expected return on risky
assets is te risk free rate
( )2 i if E ER am s a a-= + -
i iE Ea a-=
fRm=( )2~ ,fER N R s
Utility is absoluteMax utility subject to budget constraint
Substituting for , because the budget constraint holds with equality.
( ) ( )1 1
,
. . . .
E2
i iE f
i iE f
k
i i
st st
aw Var wMaxa a
a a³ +
-
( ) ( )2 2
+ 2rf
iE
i i iE E Ek R
aMaxa
ms
a a a- -
( ) ( )1 1expi i iU w aw=- -
i if Eka a= -
Taking the first order condition, we have
This is the standard result
2 iEfR a am s= +
Basically, if people are benchmarking against the market, =1 has no risk
Then, Through arbitrage
Which means, trivially, that all assets have the same return
22 21 mi i
1 1i iRisk Risk
Return 1 Return 1i i
Search for alpha like ‘Optimal stopping problem’
Sample various ‘investments’ xj where xj~N(,2 )
Each investment costs c>0You get T draws (eg, 100)At any stage n, can stop and receive xn in
until TOptimal to sample until xn>k(c,n, 2 ,T),
where k is the criterion for stopping
As the cost of sampling goes up, propensity to stop searching increases
As the variance of the sampling information increases, the propensity to stop searching decreases
As the time left in the draw goes down, the propensity to stop increases
0kc
20k
0kj
You are willing to pay to take risk because you get value from the extra sampling in many cases (c>0)
Sampling more than once, for most parameters, will be the optimal solution for most situations
As time goes on, the ability to take such risk decreases because the benefits are not as great
High variance increases value for searchForms our intuition
Trying something to see if you have alphaTrying out for footballWriting poetryAppearing on American Idol
Most fail, miserably. Why it hurts to fail, it reflects on you.
Finding your best fit has big payoffsOutside of organized sampling as in school,
generally people will tell you, you have no chance
“That the automobile has practically reached the limit of its development”
Scientific American 1909 “Heavier-than-air flying machines are impossible”
Lord Kelvin 1895 “There is no reason anyone would want a computer in their
home”
Ken Olson 1977 “We stand on the threshold of rocket mail”
US postmaster general Arthur Summerfield 1959 “Nuclear-powered vacuum cleaners will probably be a reality in
10 years”
Alex Lewyt President of Lewyt Vacuums, 1955
People overconfident when they search for alpha
Good meta-strategy , bad investment strategyLeads to excess demand for super risky
assets
AAA-BBB spread, 3mo to 2 yr T-billsNo alpha searching herePrescience too hard to prove
Everyone needs some amount of safety assets, cash
Cash is a ‘medium of exchange’, a property many investments do not haveRepos (cash) have T-bills, AAA securities as
collateral
Risk
ExpectedReturn
No Alpha Possible, no hope,no benchmarking
Expensive Alpha Searching,Too much hope
Alpha Possible,Benchmarking