100 likes | 252 Vues
This session from Math 479 at the University of Illinois, led by Professor Rick Gorvett, focuses on the intricacies of risk classification and ratemaking relativities in actuarial mathematics. Key topics include classification factors, territorial ratemaking, and how to calculate premiums for varying policy limits. The session emphasizes the importance of determining class rates, indicated overall rate changes, and the selection of reliable rating variables. Understanding these concepts is crucial for accurate pricing and risk management in the insurance industry.
E N D
Math 479 / 568 Casualty Actuarial Mathematics Fall 2014 University of Illinois at Urbana-Champaign Professor Rick Gorvett Session 9: Risk Classification September 30, 2014
Agenda • Ratemaking “relativities” • Risk classification
Ratemaking “Relativities” • Three kinds of relativities • Classification • Territorial • Increased limits • Classification ratemaking • One class serves as the “base class” (relativity = 1.00) • Rates for other classes are keyed off of the base class rate • Class rate = base rate × class relativity factor
Ratemaking “Relativities” (cont.) • Classification ratemaking (cont.) • Ratemaking process • Determine indicated overall rate change • Determine on-level premium for each class • Convert on-level EP by class to a base-class-equivalent by dividing by the existing class relativities • Determine loss ratio for each class, using base-class-equivalent on-level EP • Determine indicated class relativities by dividing each class’s loss ratio by the base class loss ratio • Use an off-balance factor to determine the base rate necessary to achieve the overall indicated rate change • If necessary, limit rate changes by class to any existing regulatory restrictions, and adjust to yield the overall indicated rate change
Ratemaking “Relativities” (cont.) • Territorial ratemaking • Very similar to classification ratemaking, conceptually and procedurally • Increased limits factors • Basic limits premium or loss cost • E.g., $100,000 per occurrence limit • Calculate premiums or loss costs for higher policy limits by multiplying the basic limits value by the appropriate increased limits factor (ILF)
Risk Classification • Differential premiums • Group characteristics determine the class • Different characteristics imply different underlying loss propensities, and thus different indicated / required premiums • Costs that may vary by group: • Losses • Risk – variation from expected values; e.g., more heterogeneity within a group implies more potential adverse selection • Expenses • Investment income – e.g., long- versus short-tailed LoBs
Risk Classification Rating Variables • Criteria for selecting rating variables • Statistical or actuarial • Accuracy and fairness • Homogeneity • Credibility • Reliability or predictive stability • Operational or practical • Objectively defined • Administrative expense • Verifiability
Rating Variables (cont.) • Criteria for selecting rating variables (cont.) • Social • Socially acceptable • Privacy issues • Causality – intuitively understandable underlying economic or risk management link of rating variable to insurance cost • Controllability • Affordability • Legal • State regulations • Federal equal protection clause