Actuarial Notes

CAS Exam MAS-II Fall 2019, Question 11

Study guide: Exam MAS-II

You are building a Linear Mixed Model to estimate the number of polices written by sales representatives in various agencies in the company. You are given the following information:

  • The number of polices written (Y_{ij}) is measured for a sales representative i who works in agency j.
  • L_j and M_j represent characteristics of individual agencies.
  • N_{ij} represents a characteristic of an individual sales representative.
  • \mu_j (as printed; the model writes u_j) is a random effect for each agency that is normally distributed with mean 0 and variance \sigma^2_{agency}.
  • \varepsilon_{ij} is a residual that is normally distributed with mean 0 and variance \sigma^2.
  • The general model specification is in the following form:
Y_{ij} = \beta_0 + \beta_1 \times L_j + \beta_2 \times M_j + \beta_3 \times N_{ij} + \beta_4 \times M_j \times N_{ij} + u_j + \varepsilon_{ij}

Determine the hierarchical model specification.

  • A) Level 1: Y_{ij} = b_{0j} + b_{1j} \times M_j + \varepsilon_{ij}; Level 2: b_{0j} = \beta_0 + \beta_1 \times L_j + \beta_3 \times N_{ij} + u_j, b_{1j} = \beta_2 + \beta_4 \times N_{ij}
  • B) Level 1: Y_{ij} = b_{0j} + b_{1j} \times M_j; Level 2: b_{0j} = \beta_0 + \beta_1 \times L_j + \beta_3 \times N_{ij} + u_j + \varepsilon_{ij}, b_{1j} = \beta_2 + \beta_4 \times N_{ij}
  • C) Level 1: Y_{ij} = b_{0j} + b_{1j} \times N_{ij} + \varepsilon_{ij}; Level 2: b_{0j} = \beta_0 + \beta_1 \times L_j + \beta_2 \times M_j + u_j, b_{1j} = \beta_3 + \beta_4 \times M_j
  • D) Level 1: Y_{ij} = b_{0j} + b_{1j} \times N_{ij}; Level 2: b_{0j} = \beta_0 + \beta_1 \times L_j + \beta_2 \times M_j + u_j + \varepsilon_{ij}, b_{1j} = \beta_3 + \beta_4 \times M_j
  • E) Level 1: Y_{ij} = b_{0j} + b_{1j} \times N_{ij} + \varepsilon_{ij}; Level 2: b_{0j} = \beta_0 + \beta_1 \times L_j + \beta_3 \times M_j + u_j, b_{1j} = \beta_2 + \beta_4 \times M_j

Answer this question and see the worked solution

Concepts tested

More questions from this set