PSY-380 Lecture Notes - Type I And Type Ii Errors, Null Hypothesis, Statistical Hypothesis Testing
Document Summary
The four steps of a hypothesis: statement of the hypothesis, setting of the criteria for a decision, collection of data and computation of sample statistics, decision making. Hypothesis testing: statistical method that uses sample data to evaluate a supposition about a population. Null hypothesis: states that in the general population there is no change, no difference, or no relationship. Alternative hypothesis: states that there is a change, a difference, or a relationship for the general population. Alpha level: probability value that is used to define the concept of very unlikely. Critical region: groups of extreme sample values are very unlikely to be obtained if the null hypothesis is true. The test statistic: indicates that the sample data are converted into a single figure to test a hypothesis. Type i error: occurs when a researcher rejects a null hypothesis that is actually true. Type ii error: occurs when a researcher fails to reject a null hypothesis that is in fact false.
