loss ratio approach: advantages
loss ratio approach: disadvantages
per occurrence excess loss
P*E*x
Premium*ELR*per occurrence charge/excess ratio
per aggregate excess loss
P*E*(1-x)*phi
phi is per aggregate charge/aggregate ratio
ultimate excess loss formula
P*E*x+P*E*(1-x)*phi
implied development approach process
implied development approach: advantages
*limited losses develop faster and is more stable than excess
implied development approach: disadvantage
-Does not explicitly recognize excess loss development
why is it appropriate to index deductible for inflation
because it keeps the proportion of deductible/excess losses constant about the limit from year to year
direct development approach
Focus on excess development directly
direct development approach: advantage
-Explicitly recognizes excess loss development
direct development approach: disadvantages
formulas for development factors for LDFL and XSLDFL
LDFL = LDF*RL/RtL
XSLDFL=LDF*(1-RL)/(1-RtL)
R: severity relativity (limited severity/unlimited severity), ratio of reported losses
R should decrease with time
these formulas can be used for CDFs and LDFs, the formula above is for CDF but can adjust to make LDF by adjusting RL
unlimited LDF formula aka credibility formula
LDF=RtL*LDFL+(1-RtL)*XSLDFL
weighted average of excess and limited LDFs
Credibility weighting/BF
-Relies on weighting indications based upon actual experience (direct development) with expected values (loss ratio approach)
U=Z*O*LDF + (1-Z)*E
O: observed loss at time t, LDF: age to ultimate, E: expected ult loss
*If set Z=1/LDF, end up with BF estimate for ultimate loss
U=O + E*(LDF-1)/LDF
*E is expected excess loss and LDF is XSLDF
credibility weighting: advantages
credibility weighting: disadvantage
-Ignores actual experience to extent of complement of credibility, may need to find weights that are more responsive to actual experience
service revenue and calculation
-Revenue associated with servicing claims under high deductible program - needs to be reflected on asset side of balance sheet
service revenue = LM*(Ult limited losses - ult excess of aggregate limit)
service revenue asset = service revenue - collected service revenue