Statistics Quiz Flashcards
(10 cards)
Which general category of statistical methods is intended to answer questions about populations by using sample data?
parameters
statistics
descriptive statistics
inferential statistics
inferential statistics
Statistical techniques that summarize, organize, and simplify data are best classified as ____ statistics.
population
sample
descriptive
inferential
descriptive
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
statistic
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
the average squared distance from the mean
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
correctly rejecting the null hypothesis
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
falsely concluded that a treatment has an effect
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
falsely concluded that a treatment has no effect
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
the size of a treatment effect or the strength of a correlation
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
True
It is always possible that patterns observed in sample data do not accurately represent patterns in the population.
True
False
True
