Unit 1
A variable that is manipulated
Independent variable
A type of distribution where the data is clustered on the left side and the tail extends to the right side
Describes the relationship between 2 variables
Correlation
=count
Formula for N
Gender is an example of what type of variable
Nominal
Reliability
Measures how spread out the data is in relation to the mean
A measure of internal reliability that tells us how closely related the items of a scale are to each other
Cronbach's alpha
sum of all data points/number of data points
Formula for mean
The process by which all the necessary information about a study is given to a person before they decide whether they want to participate
Informed consent
A type of research that uses random assignment
Experimental research
This statistic is used when making an interpretation about the population
95% CI
The difference between the actual value and the predicted value
Residual
(X-M)/SD
Formula for z-score
Measure the extent to which items on a scale correlate with each other
Inter-item/internal reliability
Revealing the purpose of a study to participants after the collection of data
Debriefing
Allows us to compare two scores from two different scales
Z-scores
Restriction of range, outliers, and non-linearity should be considered when interpreting which statistic?
Pearson's r
√(X-M)2/(N-1)
Formula for standard deviation (sample)
Measures the degree to which results from an experiment apply to the real world
Ecological validity
Compares responses on the first half of a scale to responses on the second half for consistency
Split-half reliability
The extent to which the characteristics of the sample do not match those of the population
Sampling error
Tells us how much of the variation in one variable can be explained by the variation in the second variable
Coefficient of determination (r2)
ΣZXZY/(N-1)
Formula for Pearson's r
This type of preliminary testing can improve the reliability of a scale
Pilot testing