# Video and Multimedia

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Hypothesis Testing

This video describes the four steps of hypothesis testing (2:08).

Power and Sample Size

Describes the basic concepts of power and sample size calculations (4:53).

Cohen's d Effect Size

This is a tutorial on how to calculate Cohen’s d or the effect size for groups with different means (4:49).

Type I and II Errors and the Power of the Test

This video discusses Type errors, Type II errors, their probabilities of occurring (α and β) and the power of a hypothesis test (8:10).

Null Hypothesis Testing

This lecture discusses null hypothesis testing, Type I error, Type II error, and p values (27:59).

Bell Curve and Null Hypothesis Testing

This lecture provides an illustrative example of null hypothesis testing and how assumptions regarding the characteristics of the normal curve allow us to make inferences from a sample to the population (26:48).

Power and Effect Size

Lecture discusses power, ways to increase power, and advantages and disadvantages of each method. Also discusses effect size, Type II errors, α, and power (43:16).

Prison Psychology and the Stanford Prison Experiment

During this NPR clip, Phillip Zimbardo discusses his famous psychology experiment and how it relates to current events. This can be applied to learning about hypothesis testing and samples within a population (10:59).

Factors that Affect the Power of a Statistical Procedure

This website includes definitions and simple explanations about the factors that affect power within a sample. Also contains links on the website to other helpful information related to this topic.

Interpreting Cohen’s d Effect Size

Provides an interactive visualization of Cohen’s d.

Effect Size Calculator

Includes effect size calculators.

The Null Hypothesis: Directional and Non-Directional Tests

This website includes an overview of the null hypothesis and directional versus non-directional tests. It provides practice problems as well.

Hypothesis Test: Difference Between Proportions

This website describes hypothesis testing, provides two sample problems, and discusses the use of the z score.