Hypothesis Testing

H₀ is the symbol for the alternative hypothesis

Predicts that the independent variable will have no effect on the dependent variable for the population

If the parametric assumptions are not met, you might make an incorrect decision about the hypothesis

Type II error: occurs when we fail to reject a false alternative hypothesis

H₁: there is a change, difference, or relationship for the general population

Predicts that the independent variable will have an effect on the dependent variable for the population

You can not prove a hypothesis

You can prove a hypothesis

The critical region boundaries for a 2-tailed test are set at ±1.96 when α=0.05

Null hypothesis (2-tailed): μ₁=μ₂

The level of significance of a hypothesis test is also called the ________

Increased power _______ type __ errors

You cannot prove a hypothesis because _______________

Which is not a parametric assumption?

Alternative hypothesis (directional test):μ₁≠μ₂

Nonparametric statistics can be divided into 3 categories: categorical, sign, and rank

The critical region boundary for a directional test is either + or -1.65 when α=0.05

Nonparametric tests are appropriate when subjects are not randomly sampled

Valid statement: fail to reject the alternative hypothesis

The investigator fails to notice an effective treatment when one indeed exists

Boundaries of the critical region are determined by the sample size

Procedures for determining whether sample data represent a particular relationship in the population

Statistics are applied to the ______________

The investigator states there is an effective treatment plan when one does not exist

Statistically significant: very unlikely to occur when the null hypothesis is true

A directional test is used when previous research has been done

Statistic method that uses sample data to evaluate a hypothesis about a population

By convention, alpha is usually set at 5% or 1%

The probability of committing a type I error is equal to the alpha level

The critical region is composed of extreme sample values that are unlikely to be obtained if H₁ is true

False negative

Inferential statistics uses sample data

What statement about nonparametric (NP) statistics is not true?

Beta (β) is the probability of committing a type II error

Power = 1-α

If sample data falls in the critical region, we then ___________ ______

Occurs when we reject a true null hypothesis

Alpha level is a probability value used to define the very unlikely sample outcomes if H₀ is true

False positive

When should nonparametric statistics be used?

Nonparametric tests are less powerful than parametric because nonparametric tests use quantitative scales of measurement

States there is no difference, change, association, or relationship