Between Subject T tests Flashcards
What type of data is used in between-subject tests?
Continuous data (scale data) e.g scores out of 10, temperature
Examples include scores out of 10 and temperature.
What question does the t test help answer?
Are two means significantly different from each other?
What does the t statistic represent?
t = variance explained by our IV / unexplained variance
What is the most common test of normality?
Shapiro-Wilk test
What does a large p value from the Shapiro-Wilk test indicate?
No significance - we want this
What is the p value threshold for the Shapiro-Wilk test to meet the assumption for normality?
Greater than 0.05
What does a one sample T-test compare?
Data from your experiment with one single number
What are the assumptions for a one sample T-test?
- Data are independent - one score per person
- Data are continuous - interval or ratio
- Data are normally distributed
What is the non-parametric alternative to a one sample T-test?
One Sample Wilcoxon signed-rank test
What is the design of an independent samples T-test?
Between subjects design
What are the assumptions for an independent samples T-test?
- Data are independent - one score per person
- Data are interval or ratio
- N of at least 12
- Data are normally distributed
- Homogeneity of Variance
What does homogeneity of variance refer to?
Is the variance in condition 1 similar to the variance in condition 2
What is Levene’s Test used for?
For equality of variance
What is the desired outcome for p value in Levene’s Test?
p > .050 = no significant difference
What does a Q-Q plot help visualize?
Homogenous data will fall roughly on the diagonal line
