Hypothesis Testing 2.0

Population

All possible cases of some entity that possesses similar characteristics.

Sample

A subset of a population selected for observation and analysis.

Sampling Error

The error that occurs when a sample does not represent the entire population.

Null Hypothesis

The hypothesis of no difference or no relationship between variables.

Alternative Hypothesis

The hypothesis that proposes a difference or a relationship between variables.

One-directional Hypothesis

A hypothesis that specifies the direction of a relationship (increase or decrease).

Two-directional Hypothesis

A hypothesis that does not specify the direction of the relationship and allows for change in either direction.

Type One Error

Rejecting a null hypothesis that is actually true; often referred to as a false positive.

Type Two Error

Failing to reject a null hypothesis that is actually false.

Alpha

The threshold of significance set for a statistical test, commonly at 0.05.

Power of a Test

The probability of correctly rejecting a false null hypothesis.

Parametric Methods

Statistical methods that assume underlying statistical distributions, often used for interval or ratio data.

Non-parametric Methods

Statistical methods used when data do not meet the assumptions of parametric tests.

Simple Random Sampling

A sampling technique where every individual has an equal chance of being selected.

Stratified Sampling

A sampling method where the population is divided into subgroups and samples are taken from each.

Convenience Sampling

A non-random sampling method where samples are taken from a group that is easily accessible.

Levine's Test

A test to determine if the variances of two groups are equal.

Census

A comprehensive count or survey of the entire population.

Rejection Region

The area in a statistical distribution where the null hypothesis is rejected.

Systematic Random Sampling

A sampling method that selects individuals at fixed intervals from a list.