AP Psychology Statistics Review

A frequency distribution

• is a way to present data visually in a table
• depicts a correlation between two variables using a histiogram
• is the same thing as a scattergram
• typically lists the frequency of each score on the horizontal axix

Your psychology professor wants to organize and summarize the scores on the first psychology test; which type of statistics is your professor most likely to use? 

• descriptive statistics
• inferential statistics
• correlational statistics
• significant statistics

You psychology professor wants to describe the average score on your first psychology test.  Which measure of central tendency is your professor most likely to use? 

• mean
• median
• mode 
• harmonic mean

Which measure of central tendency is obtained by adding all the scores and dividing that total by the number of scores?

• mode
• median
• mean
• range

Scores pile up at the low end of the scale in 

• a negatively skewed distribution
• a positively skewed distribution
• any skewed distribution
• a normal distribution

The marketing agent for a professional sports franchise conducts a survey asking people how much they support the construction of a new sports stadium. Almost everyone who takes part in the survey indicates they are strongly in favor of a new stadium; there are just a few respondents who think a new stadium would be a bad idea.  When the results from the survey are plotted in a histogram, the distribution will be 

• positively skewed
• symmetrical
• impossible to predict without more information
• negatively skewed

Dr. Kleiman gives an exam where most of the students receive failing grades and only a few students receive high scores.  When the exam scores are plotted, the distribution will be

• positively skewed
• negatively skewed
• symmetrical
• impossible to predict without more information

In a strongly skewed distribution, the best indicator of central tendency is usually the

• mean
• median
• mode
• standard deviation

When scores are "bunched up"in the center of a distribution, the

• mean will be relatively low

• standard deviation will be relatively low

• correlation coefficiaent will be a negative number

• standard deviation will be relatively high

The standard deviation

• indicates the average difference between each score in a group and the mean for that group of scores
• reveals the degree of skew for a a group of scores 
• is sensitive to scores at the extremes of a distribution of scores
• is used to determine whether a data set is positively or negatively skewed