Motor insurance portfolio analysis using PCA, Chi-Square testing and Poisson modelling in R | STAT1011Y | University of Mauritius
# Motor Insurance Portfolio Analysis
**STAT1011Y – Statistical Methods | University of Mauritius | 2025/2026**
A group statistical analysis of a 1,200-policy motor insurance portfolio and daily claim count data, completed as part of the BSc Actuarial Studies programme. All analysis was done in R.
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## Project Overview
| Problem | Topic | Method |
|---|---|---|
| 1 | Risk Profiling & Dimension Reduction | Principal Component Analysis (PCA) |
| 2 | Association Between Categorical Variables | Pearson's Chi-Square Test of Independence |
| 3 | Claim Frequency Analysis | Poisson Goodness-of-Fit Test |
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## Problem 1 – Risk Profiling (PCA)
Explored the underlying risk structure of the motor insurance portfolio using PCA on 8 variables (age, vehicle age, premium, no-claims discount, past claims count, past total paid, annual mileage, engine power).
**Key findings:**
- 3 principal components retained, explaining ~55% of total variance
- PC1 captures claims history vs. no-claims discount (high-risk vs. low-risk policyholders)
- PC2 captures vehicle power and usage patterns
- PC3 captures driver and vehicle age effects
- Robustness confirmed by repeating PCA without premium — component structure remained stable
- Distinct risk profiles identified: Young Power Drivers, High-Mileage Commercial Users, Aged Risk, Low Discount High Claim
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## Problem 2 – Chi-Square Test of Independence
Investigated whether claim type (Bodily Injury, Other, Property, Windscreen) and transmission type (Automatic, Manual) are independent.
**Key findings:**
- χ² = 8.0551, df = 3, p-value = 0.0449
- Rejected H₀ at the 5% level — evidence of association between claim type and transmission type
- Standardised residuals showed Windscreen claims on Automatic vehicles (residual = 2.45) as the primary driver of the association
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## Problem 3 – Poisson Claim Frequency Analysis
Assessed whether daily claim counts from 365 days of portfolio data follow a Poisson distribution.
**Key findin …