Exam 81: Understanding Descriptive and Inferential Statistics for Psychological Research

Which of the following would tell us the percentage of variance in one variable that can be accounted for by knowing the other variable?

Students' hat sizes and their college grades would be a

A sample is

A single number that describes a "middle score" is a(n)

Which of the following is the index of how much a typical score differs from the mean of a group of scores?

For his research study,Dr.Safar wants to make sure that his sample is a representative one.The most effective way for him to do this is to

Matt is using a single score that describes how scattered or "spread out" his distribution of scores is.Matt is using a measure of

Direct measurement has shown such characteristics as height,memory span,and intelligence to be distributed approximately along a normal curve.

An important advantage of the standard deviation is that it can be used to "standardize" scores in a way that gives them greater meaning.

You have just read a story in the media that reports a correlation of .25 between two factors.The percent variance for this correlation would be

Define a z-score,and explain how it is calculated in the following example: Abby had a score of 75 on a test with a mean of 70 and a standard deviation of 5.What is her z-score?

Gordon is trying to find the percent of variance in one measure that is accounted for by knowing another measure. In order to do this,Gordon must square the

A psychologist is interested in the effectiveness of a new method for teaching math to third graders.She is testing it on several third grade classes.In this example,the population is

Twenty psychology students took a 10-point practice test.Their scores were as follows: 3,3,4,5,5,5,6,6,6,6,8,8,9,9,9,9,10,10,10,10.What would be the median?

Graphical statistics

Which of the following correlation coefficients indicates the weakest relationship?

If there is a correlation of .78 between socioeconomic status and IQ score,which of the following statements is TRUE?

After administering a unit test to her psychology students,a college professor calculates the mean and range for this test in order to better understand the performance of her students on the material in this unit.This professor is using _______ statistics.

The variability of a set of scores refers to which aspect of those scores?

It is important to keep in mind that correlation _______ causation.