Which of the following describes what a confidence interval does?

A population of scores has µ = 80.  In this population, a score of X = 86 corresponds to z = +2.00.  What is the population standard deviation?

For an independent-measures t statistic, what is the effect of increasing the number of scores in the samples?

Which of the following is an accurate definition of a Type II error?

If random samples, each with n = 9 scores, are selected from a normal population with µ = 80 and σ = 36, then what is the expected value for the distribution of sample means?

What does k signify in dfBG= k-1 for Two-Factor ANOVA?

In an experiment to determine whether seeding clouds with silver iodide increases rainfall, 52 clouds were randomly assigned to be seeded or not. The amount of rain they generated was then measured (in acre-feet). Would we use the first line or the second line of the independent-samples t-test results from SPSS?  

Which of the following describes what a confidence interval does?

A college professor reports that students who finish exams early tend to get better grades than students who hold on to exams until the last possible moment.  The correlation between exam score and amount of time spent on the exam is an example of ____.

On average, what value is expected for the F-ratio if the null hypothesis is true?