Chapter 9: Estimating the Value of a Parameter

Question 1

point estimate

Answer 1

single statistic that estimates a parameter

Question 2

confidence interval

Answer 2

range of numbers in which we are some % certain the parameter lies

Question 3

level of confidence

Answer 3

expected proportion of intervals that will contain the parameter if a large number of different samples is obtained

Question 4

Conditions to construct the confidence interval for p

Answer 4

np̂(1 - p̂) ≥ 10 and 20n ≤ N

Question 5

Formula for confidence interval for p

Answer 5

p̂ ± z_α/2 sqrt(p̂(1-p̂)/n)

Question 6

Formula for minimum sample size needed for a particular level of confidence

Answer 6

n = p̂(1 - p̂) ((z_α/2) / E)^2

Question 7

general form for the confidence interval for a population parameter

Answer 7

(point estimate) ± (critical number)(standard error)

Question 8

standard error [of the mean]

Answer 8

standard deviation of the sampling distribution of x̄

Question 9

(1 - α)100% Confidence Interval for μ

Answer 9

x̄ ± t_α/2 * (s/sqrt(n))

Question 10

(1 - α)100% Confidence Interval for σ

Answer 10

( sqrt( (n - 1)s^2 / χ^2_α/2 ) , sqrt( (n-1)s^2 / χ^2_1-α/2 ) )