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Statistic

a characteristic of the sample, such as the mean of the sample scores

Parameter

Describes a characteristic of the population; such as the mean of all population scores

Inferential statistics

Techniques used to make generalizations about the population from which the sample was drawn; to determine the likelihood that the sample result is due to chance/error

Hypothesis testing

Method of using sample data to evaluate a claim about a population parameter; a method for making rational decisions about the reality of our sample results

Hypothesis

Statement about the population parameter

Null hypothesis

There is no effect, no relationship, no difference, nothing real in the population

Alternative hypothesis

There is an effect, a relationship, a difference, something is happening.

Type 1 error

incorrect rejection of the null hypothesis.

Type 2 error

Incorrect acceptance of the null hypothesis.

Probability of replication

the probability that an effect will be seen again if the study is repeated

Power

The likelihood of correctly detecting a real effect (correct rejection of null); in other words, the likelihood of getting a statistically significant result