Mod 8 Statistics Practice

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

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

The symmetric, bell shaped curve that represents the pattern in which many human characteristics are dispersed in the population is known as

• scatter plot
• normal distribution
• frequency polygon
• histogram

Inferential Statistics

• Statistical analysis of two or more sets of numerical data to reduce the possibility of error in measurement and to determine if the differences between the data sets are greater than chance variation would predict

• A number that represents the strength and direction of a relationship existing between two variables

• A distribution of scores in which scores are concentrated in the low end of the distribution

• A distribution of scores in which scores are concentrated in the high end of the distribution

Statistically Significant

• Referring to differences in data sets that are larger than chance variation would predict

• A number that represents the strength and direction of a relationship existing between two variables