statistical analysis

Question 1

Which general category of statistical methods is intended to answer questions about populations by using sample data?

​parameters
​statistics
​descriptive statistics
​inferential statistics

Answer 1

parameters
​statistics
​descriptive statistics
​-inferential statistics

Question 2

Statistical techniques that summarize, organize, and simplify data are best classified as ____ statistics.

​population
​sample
​descriptive
​inferential

Answer 2

​population
​sample
​-descriptive
​inferential

Question 3

A researcher records the change in weight (gain or loss) during the first semester of college for each individual in a group of 25 freshmen, and calculates the average change in weight. The average is an example of a ____.

​parameter
​statistic
​variable
​constant

Answer 3

parameter
​-statistic
​variable
​constant

Question 4

What is the definition of variance?

​the sum of the scores divided by the number of scores
​the average distance from the mean
​the square root of the average distance from the mean
​the average squared distance from the mean

Answer 4

​the sum of the scores divided by the number of scores
​the average distance from the mean
​the square root of the average distance from the mean
​-the average squared distance from the mean

Question 5

What outcome is likely to occur for a hypothesis test evaluating a treatment that has a very large and robust effect?

​a Type I error
​a Type II error
​correctly rejecting the null hypothesis
​correctly failing to reject the null hypothesis

Answer 5

a Type I error
​a Type II error
​-correctly rejecting the null hypothesis
​correctly failing to reject the null hypothesis

Question 6

A Type I error means that a researcher has ____.

​falsely concluded that a treatment has an effect
​correctly concluded that a treatment has no effect
​falsely concluded that a treatment has no effect
​correctly concluded that a treatment has an effect

Answer 6

-falsely concluded that a treatment has an effect
​correctly concluded that a treatment has no effect
​falsely concluded that a treatment has no effect
​correctly concluded that a treatment has an effect

Question 7

A Type II error means that a researcher has ____.

​falsely concluded that a treatment has an effect
​correctly concluded that a treatment has no effect
​falsely concluded that a treatment has no effect
​correctly concluded that a treatment has an effect

Answer 7

falsely concluded that a treatment has an effect
​correctly concluded that a treatment has no effect
​-falsely concluded that a treatment has no effect
​correctly concluded that a treatment has an effect

Question 8

Values such as Cohen’s d or r2 (the percentage of variance accounted for) are used to measure ____.

​the validity of a hypothesis test
​the risk of committing a type I error
​the size of a treatment effect or the strength of a correlation
​the level of significance

Answer 8

​the validity of a hypothesis test
​the risk of committing a type I error
​-the size of a treatment effect or the strength of a correlation
​the level of significance

Question 9

The goal of a hypothesis test is to demonstrate that the patterns observed in the sample data represent real patterns in the population and are not simply due to chance or sampling error.​
True
False

Answer 9

True

Question 10

It is always possible that patterns observed in sample data do not accurately represent patterns in the population.​
True
False

Answer 10

true