Kreps - Riskiness Leverage Models Flashcards
each insurer has number of different liabilities and assets which are all supported by
a single pool of shared capital
typically the mean is supported
by the reserves
variability is supported
by surplus
capital often has to be allocated but
really it is the allocation of cost of capital which is relevant
allocation of cost of capital which is relevant can help
derive an appropriate risk load
Several desirable qualities for an allocatable risk load formula
- it can be able to be allocated down to any level
- risk load of any sum of random variables should = sum of risk loads allocated individually
- same additive formula can be used to calculate risk load for any subgroup or groups of groups
if desirbale qualities apply
senior management would be able to allocate capital to regions and then have regional management allocate their share of capital to the LOBs
-these allocations @ LOB level should add to original capital
Riskiness leverage ratio
arbitrary selection by management, allowing their views towards risk be incorporated
capital to support X (sum of liabilities)
C = u + R
u = mean of X
R = risk load for X
we can think of this in balance sheet terms: capital would be = total assets, mean = booked liabilities, risk load = surplus
Kreps states that riskiness leverage models have the following form
-should use Monte Carlo simulation to calculate the above integrals
riskiness leverage L depends only
on sum of individual variables
riskiness leverage models equations indicate
that some variables may have negative risk loads if they are below their mean when riskiness leverage is large
desirable feature of variable that have negative risk loads
these variables can be considered to be hedges -> should not require a risk load and in fact should reduce overall required risk load
Several different ways to express the equation for R
- expresses the risk load as the probability weighted average of risk loads over outcomes of the total loss
- this riskiness leverage factor would reflect that all dollars are not equally risky
- those that trigger analyst or regulatory tests would be considered to be more risky - expresses risk load as integral over risk load density
- advantages of this formula is that it shows which outcomes contribute most to risk load
Properties of Risk Load
- risk load for a constant c, is 0; R(c)=0
- risk load with scale with a currency change; R(λX)=λR(X)