Exam 81: Understanding Descriptive and Inferential Statistics for Psychological Research

A useful tool for interpreting the correlations encountered in the media and the psychological literature is to square the correlations to obtain the

An entire set of subjects,objects,or events belonging to a particular category is called a

Dots connected by straight lines are to a frequency polygon as a bar graph is to a

Dr.Little is interested in studying the effects of a new medication on children with asthma between the ages of six and 12.She gets permission to try the medication on asthma patients in several hospital clinics.In this example,the sample includes children

What percent of all cases are found between an SD of +1 and an SD of -1 on a normal curve?

You have found a correlation coefficient of +.70 between the number of days students attend class and their grade point averages.Describe what this correlation means both in its strength and direction;determine the percent of variance and explain what it means;and explain why this correlation does not prove causation between class attendance and grade point average.

You have been asked to determine what the "typical" salary is for the employees at a small company.After looking at a list of the salaries,you note that the CEO and three vice-presidents make significantly more than any of the other 50 employees.Which descriptive statistic would be the LEAST affected by these four high salaries and would be the best measure to use to determine the "typical" salary?

Inferential statistics are used to

A researcher discovers two drugs that lower anxiety in agitated patients.However,one drug consistently lowers anxiety by moderate amounts,whereas the second sometimes lowers it by large amounts,sometimes has no effect,or may even increase anxiety in some patients.Although there is not an overall difference in the average (mean)amount of anxiety reduction,an important difference does exist between the two drugs.This difference would best be shown by using

If the mean on a test is 90 and the standard deviation is 10,a person with a z-score of -1.0 scored 110 on the test.

If the mean of a test is 80 and the standard deviation is 10,a person with a z-score of -2.0 scored which of the following on the test?

A bell-shaped distribution,with a large number of scores in the middle,tapering to very few extremely high and low scores is known as a negatively-skewed curve.

When we want to generalize from the behavior of a small group to a large group,we must rely on

The fewer absences that students have,the higher their grade point average.This illustrates a negative relationship.

Which of the following is NOT an example of a question that could be answered using a correlational study?

The simplest way of visualizing a correlation is to construct a scatter diagram.

Which of following represents the point in a group of scores where half the values of the group of scores fall below the median and half fall above?

There are 10 students in the pre-kindergarten class.Each student is shown eight colors and asked to name them.The number of colors correctly named by each student is: 8,8,8,8,7,7,6,6,5,4.What would be the mode?

The fewer days that students attend class,the lower their grades.This would be a

On a normal curve,99 percent of all the cases would be found between which two standard deviations (SDs)?