Statistics 101 Problem Set #7 Fall 1999
This homework is to be done individually. It is due on the last day
of class.
-
- Exercise 7.4 page 268
- Exercise 7.5 page 268
- Taxicabs are numbered from 1,2,...,N. We want to estimate N, the
total number of taxicabs. We will observe n (n less than N)
cabs. Denote their number by Y1,...,Yn.
We consider two estimators for N:
- Estimator 1 is (2 Y-bar - 1) where Y-bar is the
average of all the Y's observed.
- Estimator 2 is Maximum of
Y1,...,Yn.
Assume that the n taxicabs that we will see is a simple random
sample of the N cabs. (Sampling without replacement). We want
to compare estimator 1 to estimator 2. To this end, assume that
N = 4 and n = 2.
- Write down the 4 choose 2 possible samples of taxi
numbers.
- Write down the sampling distribution of teach of the
estimators. (Sketch the probability distribution function.)
- Which of the estimators is unbiased? Note that the true
answer is N = 4.
- Which estimator is closer to 4 on the average, where
closeness is measured by
(estimate - 4)2?
-
- Exercise 7.15 page 273
- Exercise 7.16 page 273
- Exercise 7.17 page 274
-
- Exercise 7.20 page 276
- Exercise 7.21 page 276
-
- Exercise 7.25 page 279
- Exercise 7.26 page 279
- Exercise 7.27 page 279
-
- Exercise 7.72 page 304
- Exercise 7.74 page 304
Last modified: Mon Nov 22 09:51:20 EST 1999