IFoA CS1 case studies
IFoA CS1 · Put your knowledge to work in context.
CS1 (Actuarial Statistics 1) is a subject within the Institute and Faculty of Actuaries (IFoA) curriculum - the professional body whose Qualify section covers becoming an actuary, the curriculum, and exams. CS1 sits in the statistics strand of the actuarial qualification, building the probability and statistical foundations that later subjects and practice-area work depend on. The IFoA CS1 case studies are 5 cases and about 3,789 words.
1No-Claims Discount: Stationary Distribution Versus a One-Year Forecast
A UK motor insurer operates a three-level no-claims discount (NCD) scheme. Level 1 carries a 0% discount, level 2 a 25% discount and level 3 a 50% discount.
804 words, about 4 min2Reinsurance Treaty: Thinning a Poisson Process When the Rate Is Not Constant
A reinsurer receives claims from a cedant under a quota-share treaty. Claims below £250,000 are classed as small and claims at or above £250,000 as large.
742 words, about 4 min3Claim Frequency GLM: Offsets, Overdispersion and an Exposure Coefficient
A motor insurer fits a Poisson generalised linear model with a log link to 1,500 policy-years of private car exposure. The linear predictor has an intercept, a driver-age factor (17-24 versus 25+), an area factor (urban versus rural) and log(exposure) as an offset.
734 words, about 4 min4Sickness Absence Durations: Kaplan-Meier, the Exponential Assumption and Informative Censoring
An insurer studies the duration in months from the start of a sickness absence to return to work for 12 income protection claimants. The recorded durations are 1, 2, 2, 4, 5 , 6, 7, 8 , 9, 10 , 12 and 15 , where an asterisk marks a censored observation: the claimant was still absent, or had left the insurer's book, at the end of follow-up.
855 words, about 4 min5Gamma-Poisson Credibility for a Small Group: Prior, Predictive and What 'Best Estimate' Means
A mutual insurer writes 40 group income protection policies covering 120 policy-years in total, over which the group generated 18 claims. Industry data for the same occupational class suggest a claim frequency of 0.50 claims per policy-year with a coefficient of variation of 0.50.
654 words, about 3 min