Psy 225 (Exam 2)

Front 1

probability

Back 1

a fraction or a proportion of all the possible outcomes.

probability of A= number of outcomes classified as A/ total number of possible outcomes

Front 2

random sampling

Back 2

requires that each individual has an equal chance of being selected and that the probability of being selected stays constant from one selection to the next if more than one individual is selected.

Front 3

sampling distribution

Back 3

a distribution of statistics obtained by selecting all of the possible samples of a specific size from a population

Front 4

distribution of sample means

Back 4

the collection of sample means for all of the possible random samples of a particular size (n) that can be obtained from a population

Front 5

sampling error

Back 5

the natural discrepancy or amount of error, between a sample statistic and its corresponding population parameter

Front 6

standard error

Back 6

standard error is the standard deviation of the distribution of sample means.

measures the standard distance between a sample mean (M) and the population mean.

tells how much error to expect if you are using a sample mean to represent a population mean

Front 7

standard deviation

Back 7

provides measure of the standard or average, distance from the mean

Front 8

alpha level

Back 8

the level of significance, the probability value that is used to define the concept of "very unlikely" in a hypothesis test

Front 9

effect size

Back 9

intended to provide a measurement of the absolute magnitude of a treatment effect, independent of the size of the sample(s) being used

Front 10

cohen's d

Back 10

mean difference/ standard deviation

Front 11

statistical power

Back 11

the probability that the test will correctly reject a false null hypothesis. the probability that the test will identify a treatment effect if one really exists

Front 12

when is a power analysis conducted?

Back 12

before the actual conducted research study