Psych 209: Chapter 4 Part 2 Vocab Flashcards
Exam 2
Null Hypothesis
The assumption that no real difference exists between the treatment conditions in an experiment or that no significant relationship exists in a correlational study
Hsub0
Alternative Hypothesis
The researcher’s hypothesis about the outcome of a study
H sub 1
Alpha Level
The probability of making a Type I error; the significance level
Type I Error
Rejecting the null hypothesis when it is true; finding a statistically significant effect when no true effect exists
Type II Error
Failing to reject the null hypothesis when it is false; failing to find a statically significant effect when the effect truly exists
Systematic Variance
Variability that can be attributed to some identifiable source, either systematic variation of the independent variable or the uncontrolled variation of a confound
Error Variance
Nonsystematic variability in a set of scores due to random factors or individual differences
File Drawer Effect
A situation in which findings of no difference fail to be published (the studies are placed in one’s files); the few studies that do find a difference and get published produce a distorted impression of actual differences
Effect Size
Amount of influence that one variable had on another; the amount of variance in the dependent variable that can be attributed to the independent variable
Meta-Analysis
A statistical tool for combining the effect size of a number of studies to determine if general patterns occur in the data
Confidience Interval
An inferential statistic in which a range of scores is calculated; with some degree of confidence (95%), it is assumed that population values lie within the interval
Power
The chances of finding a significant difference when the null hypothesis is false; depends on alpha, effect size, and sample size
1- beta
