CHAPTER 4: Statistical Inference - created from Mind Map

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Hypothesis

Hypothesis Testing

One-sample hypothesis tests

Two Sample Hypothesis Tests

Analysis of variance

Nonparametric methods: Chi square test of independence

Null hypothesis

Alternative hypothesis

reject H0

fail to reject H0

One-tailed tests

Step 1: Formulate the hypothesis to test by stating null and alternative hypotheses

Step 2: Select the significance level

Step 3: Select and calculate the test statistics

Two-tailed test

Step 4: Determine the decision rule

Step 5: Draw a conclusion

Errors

Type I error

Type II error

Independent

Dependent

Samples are selected at random

The scores of one samples does not affect the other

Samples are related to each other

Occur in two scenarios

To compare the means of more than two independent populations

Assumptions of ANOVA

1. are randomly and independently obtained

2. are normally distributed

3. have equal variances

To determine two categorical variables are independent

Chi square test for independence tests the following hypotheses

H0: the two categorical variables are independent – not related

H1: the two categorical variables are dependent – related

Step 2: expected frequency

Step 1: observed frequency

Step 3: chi-square statistics