Probability, null hypothesis significance testing and chi square (3)

Research methods and statistics lecture 3

What does inferential statistics help us do?

It helps us make inferences about a population based on random sample data.

What is the null hypothesis denoted as?

The null hypothesis is denoted as H0.

What is the common significance level (alpha level) typically used in psychology?

The common significance level is typically set at 5%.

What can a p-value less than 0.05 indicate?

It indicates that the result is considered statistically significant.

What do effect sizes tell us?

Effect sizes tell us the magnitude of the difference or similarity in correlations.

What are the two types of inferential statistics mentioned?

The two types are Frequentist and Bayesian statistics.

What hypothesis is predicted by the alternative hypothesis?

The alternative hypothesis predicts a difference

What are the two types of hypotheses classified by direction?

They are directional (one-tailed) and non-directional (two-tailed) hypotheses.

What does a small p-value (p < .05) suggest?

It suggests a higher chance that a difference/association/effect exists.

What does the chi-square test assess?

The chi-square test assesses the relationship between two categorical variables.

What is a chi-square test of independence also known as?

It is also known as Pearson's chi-square test.

What is the significance of a high p-value (p > .05)?

It indicates a higher chance that no difference/association/effect exists.

What is the relationship between effect sizes and p-values?

Effect sizes indicate the strength of an effect

What is the formula for calculating degrees of freedom for the chi-square test?

The formula is df = (r-1)(c-1)

What must the assumed differences for the null and alternative hypotheses be?

The null (H0) assumes no difference

What are the assumptions for conducting a chi-square test?

Frequencies must be unique

What does a large difference between observed and expected frequencies suggest?

It suggests an association between the two categorical variables.

What type of data do chi-square tests typically use?

Chi-square tests typically use nominal (and sometimes ordinal) level data.

What does interpreting p-values help determine?

It helps determine whether the findings are statistically significant.

How does sample size affect significance?

A larger sample size can lead to misleading results if not sufficient data points are used appropriately.

What does a one-tailed test concentrate on?

A one-tailed test concentrates the significance level on one tail of the distribution.

What does chi-square analysis compare?

It compares observed frequencies to expected frequencies.

What implications do small p-values have for researchers?

Small p-values suggest that findings are less likely to be due to random chance

What does the term "statistically non-significant" imply?

It implies that there is insufficient evidence to conclude that a true effect exists.

Why is it important to consider effect sizes in research?

Effect sizes provide insight into the practical significance of research findings beyond just statistical significance.

What happens if assumptions for the chi-square test are not met?

The interpretation of the results becomes less valid.

What is one limitation of p-values mentioned in the text?

They can be misinterpreted to mean something about the likelihood of the alternative hypothesis being true.

How do descriptive statistics aid researchers?

They provide a summary of data characteristics