Stat 4620

Stat 4620: Introduction to Mathematical Statistics

Instructor:  Joshua D. Naranjo
E-mail: joshua.naranjo@wmich.edu
Phone: (269)387-4548
Office: 5507 Everett Tower
WEEK 13
Thursday April 18 Tuesday April 16
WEEK 12
Thursday April 11
  • Notes (Section 6.5: Multiparameter testing)
  • Homework 21: Problem 6.5.2 (7th Ed) or 6.5.4 (8th Ed)

Tuesday April 9

  • Notes (Section 6.4: Multiparameter estimation)
  • Homework 20
    1. Find the information matrix I(mu, sigma^2) directly.
    2. Show: Var(S^2)= 2 sigma^4/(n-1) where S^2 is the unbiased sample variance. (Hint: (n-1)S^2/sigma^2 has a chi-square distribution with n-1 degrees of freedom.)

WEEK 11
Thursday April 4
  • Notes (Section 6.3 con't: Asymptotic distribution of LRT, other MLE-based tests)
  • Homework 19
    Given the following sample of size 20 from a Poisson distribution with mean Θ,
          9, 12, 9, 5, 7, 5, 7, 9, 7, 4, 7, 8, 8, 10, 6, 8, 5, 5, 8, 7
    test H0: Θ=8 against H1:Θ ≠ 8, using
    1. -2 ln(Λ)
    2. Wald test
    3. Scores test
Tuesday April 2
  • Notes (Section 6.3: The Likelihood ratio test)
  • Homework 18
    1. Problem 6.3.8 (7th Ed) or 6.3.9 (8th Ed)
    2. Problem 6.3.10 (7th Ed) or 6.3.11 (8th Ed)
WEEK 10
Thursday March 28
  • Notes (Section 6.2: Likelihood-based confidence intervals, Delta Method)
  • Homework 17: Given a random sample (x1,...,xn) from N(0, theta)
    1. Construct a likelihood-based confidence interval for the population variance theta.
    2. Construct a likelihood-based confidence interval for the population standard deviation sqrt(theta).
    3. Conduct a simulation in R by generating n=20 from N(0, 16). Calculate confidence intervals for theta and sqrt(theta) and confirm that coverage levels are approximately .95.
Tuesday March 26
  • Notes (Section 6.2: Aymptotic normality and efficiency of mle)
  • Homework 16
    1. Problem 6.2.10
    2. Simulation of ARE
      1. Generate 30 observations from Laplace distribution.
        • Calculate the mean and median
        • Repeat 1000 times, and confirm that ARE(median, mean)=2.0
      2. Generate 30 observations from N(0,1) distribution.
        • Calculate the mean and median
        • Repeat 1000 times, and confirm that ARE(median, mean)=0.64
WEEK 9
Thursday March 21
  • Notes (Section 6.2: Information and Rao-Cramer Lower Bound)
  • Homework 15
    1. Problem 6.2.7 (a), (b)
    2. Problem 6.2.8 (a), (b)

Tuesday March 19

  • Notes (Section 6.1: Maximum likelihood theory)
  • Homework 14 R solution
  • Homework 14: Simulation
    1. Generate 100 observations from Normal distribution.
      • Calculate the mle under normal, Laplace, and logistic
      • Repeat 1000 times, and compare the simulated variance of the three estimators. Which one has smallest variance?
    2. Repeat (1) for 100 observations from Laplace. Which estimator has smallest variance?
    3. Repeat (1) for 100 observations from Logistic. Which estimator has smallest variance?
WEEK 8
Thursday March 14
  • Notes (Section 4.9: Bootstrap)
  • Homework 13
    1. Problem 4.9.6 (7th Ed) or 4.9.7 (8th Ed)

Tuesday March 12

  • Notes (Section 4.8: Monte Carlo Method)
  • Homework 12
    1. Problem 4.8.1
    2. Problem 4.8.6 (Generate and print a sample of n=15 observations from given pdf. Calculate the mean and sd of the sample, and compare to the true mean and sd.)
WEEK 7
Thursday Feb 21
  • Notes (Section 4.7: Chi-square tests: Homogeneity and independence)
Tuesday Feb 19
 

Department of Statistics
3304 Everett Tower
Western Michigan University
Kalamazoo MI 49008-5152 USA
(269) 387-1420 | (269) 387-1419 Fax
stat-webmaster@wmich.edu