Reading 10: Sampling and Estimation

Question 1

Standard Error of the Sample Mean

(population standard deviation known)

10.1

Answer 1

Question 2

Standard Error of the Sample Mean

using sample standard deviation

10.2

Answer 2

Question 3

Sample Variance

Sampling and Estimation

10.3

Answer 3

Question 4

Confidence Intervals for Population Mean

Normally Distributed Population with Known Variance

Sampling and Estimation

10.4

Answer 4

A 100(1-alpha)% confidence interval for population mean µ when we are sampling from a normal distribution with known variance o² is given by the formula:

Question 5

Confidence Intervals for Population Mean

The z-Alternative (Large sample, unknown population variance)

Sampling and Estimation

10.5

Answer 5

A 100(1-alpha)% confidence interval for population mean µ when we are sampling from any distribution with unknown variance and when sample size is large is given by:

Question 6

Confidence Intervals for Population Mean

t - Distribution (Large sample, unknown population variance)

Sampling and Estimation

10.6

Answer 6

If we are sampling from a population with unknown variance and either of the conditions below holds:

• The sample is large, or
• The sample is small but the population is normally distributed, or approximately normally distributed

then a 100(1-alpha)% confidence interval for population mean µ is given by:

Question 7

Standard Error of the Sample Mean

Sampling and Estimation

10.xtra

Answer 7