Estimates and Sample Sizes Statistics

A statistic used to estimate a parameter is an ____________ if the mean of its sampling distribution is equal to the value of the parameter being estimated.

• unbiased estiamtor

• biased estimator

• highly variable

• less variable

Which of the following is an example of an interval estimate?

• point estimate 

• critical value

• confidence interval

• statistic

Complete the equation: 
point estimate +/- _____

• standard deviation

• margin of error

• critical value

• confidence level

Increasing the sample size __________ the confidence interval. 

• increases

• decreases

• does not affect

• there is not enough evidence to determine the answer

What can you do to reduce the margin of error? 

• increase the confidence level

• decrease the confidence level

• increase sample size

• decrease sample size

Given the interval (1.2, 1.8), what is the point estimate and the margin of error? 

• 1.5, 0.6

• 1.5, 0.3

• 1.2, 0.3

• 1.2, 0.6

In a recent poll of 803 randomly selected baseball fans in Connecticut, 44% said their favorite team was the Yankees. If researchers wanted to reduce the margin of error to at most 2%, how many baseball fans do they have to randomly select? 

• 1564

• 2367

• 803

• 3170

Construct a 90% confidence interval of a random sample size of 19 cows with a mean of 155.526 and a standard deviation of 19.993. 

• (146.54, 164.52)

• (147.57, 163.48)

• (147.59, 163.46)

• (143.69, 167.36)

A __________ gives an interval of plausible values for the _____________. 

• confidence interval, statistic

• point estimate, parameter

• point estimate, statistic

• confidence interval, parameter

What critical value t* is used in constructing a 99% confidence interval based on n = 12 randomly selected observations. 

• 3.106

• 3.055

• 2.58

• 1.96