This preview shows pages 1–4. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.
View Full DocumentThis preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
Unformatted text preview: STA 103 Exam 2 Spring 2008 I. H. Dinwoodie NAME Calculator allowed, closed book. STA103 Spring 2008 E2 1 Circle True or False. (1 point each) 1. The population of American women in 1975 had incomes that averaged = 10, with standard deviation = 7 (in units of $10,000). A random sample of 1,000 women was drawn. (a) T The sample mean is an unbiased estimator of . (b) F The sample variance s 2 is a biased estimator of 2 . (c) F The probability distribution of the sample mean X has a density that resembles the probability histogram of the population. (d) F The variance of the sample mean is the same as the variance of the population. (e) F A 95% confidence interval for is wider than a 99% confidence interval for . (f) F A 99% confidence interval for will always contain the mean . (g) F The mean squared error (MSE) of the sample mean for estimating is 2 . (h) F The mean squared error (MSE) of the sample mean for estimating is greater than the MSE of a single draw. (i) T The sample mean has a probability distribution that is bellshaped and is more tightly concentrated around than the distribution of the population. (j) T The probability histogram of the sample should resemble the prob ability histogram of the population. STA103 Spring 2008 E2 2 2. (4 points) At a large Midwest factory, 4 men and 4 women on the assembly line2....
View
Full
Document
This note was uploaded on 09/29/2008 for the course STAT 103 taught by Professor Dinwoodie during the Spring '08 term at Duke.
 Spring '08
 Dinwoodie
 Statistics, Probability, Standard Deviation

Click to edit the document details