Stats Final Exam

Which of the following best describes the goal of estimation?

to narrow in on the true population mean by defining limits within which it is likely to be contained

3 steps to creating any CI

1. Compute sample mean and standard error 2. Choose CI and find critical values 3. Compute the formula

A researcher reports with 90% confidence that 31% to 37% of Americans believe in ghosts. What is the point estimate for this interval?

34%

One Sample T Test Confidence Interval

Formula : M +- t (sm) Find sm by doing sd / square root n df = n - 1

One Sample Z Test Confidence Interval

Formula : M +- z (om) Find om by doing o / square root next

2 Independent Sample T Test Confidence Interval

Formula : M1 - M2 +- t (Sm1 - m2) df = n - 2

Related Sample T Test

Formula : MD + t (Smd) Df = n - 1

A point estimate is typically reported with an interval estimate. Why?

More certainty. Higher confidence.

If the value stated by a null hypothesis is ______ the confidence interval, then the decision would likely be to reject the null hypothesis.

Outside

If the null hypothesis is inside the confidence interval, then the decision was likely to ______ using hypothesis testing.

Retain the null

Which of the following explains why point estimation can be a useful procedure to estimate a population mean?

The sample mean is equal to the population mean on average and the sample mean is an unbiased estimator of the population mean.

If the value stated by a null hypothesis is ______ the confidence interval, then the decision would have likely been to retain the null hypothesis.

Within