psych stats

ordinal scale of measurement

Data are assigned to categories that can be ranked.

Parameter

a characteristic, usually a numerical value, that describes a population is called a

statistic

a characteristic, usually a numerical value, that describes a sample is called a

distribution of sample mean

a distribution of sample means for all possible random samples of a specific size that can be obtained from a population

sample

a researcher is interested in the eating behavior of rats and selects a group of 25 rats to be tested in a research study. The group of 25 rats is an example of a

population

a researcher uses an anonymous survey to investigate the study habits of American college students. All American college students, the entire group of interest to the researcher, is an example of a(n)

what describes a hypothesis test?

an inferential technique that uses the data from a sample to draw inferences about a population

what is a type II error

failing to reject a false null hypothesis

what does the z score for a raw score indicate

how many standard deviations a raw score is from the mean

what describes the effect of increasing the alpha level from .01 to .05

increases the risk of a type 1 error

the standard error of the mean (or standard error)

indicates how much distance is expected between a sample mean and the population mean

what is a type 1 error

rejecting a true null hypothesis

sampling error

the difference between the results of random samples taken at the same time

if a researcher is using a t statistic to test a null hypothesis about a population, what information is needed from the population to calculate the t statistic

the t statistic does not require any information about the population