LEARNING CHECK: Review & Integration for Chapters 1-3.

How are Z-scores related to Prediction?

1. Need Zx scores to make prediction. What you predict is a Zy score.

2. Both have to do with single scores-- finding where a single score is in a distribution, or guessing where a single score is in a distribution, based on correlation of one variable with another.

How are Mean and Variance similar?

1. Both are parameters

2. Both are calculated using formulas that take every score into account

3. Both are averages: the average of the X scores, or the average of the (X-M)² --the squared deviations of X scores from the mean

How are they different?

1. Mean is a measure of central tendency; variance of variability

2. You need to know the mean to calculate the variance; the opposite is not true

What do a histogram and a scatterplot have in common?

1. They are both visual representations of distributions

2. They both show two dimensions

How are they different?

1. One displays information about one variable; the other displays information about two variables measured on the same objects or persons.

2. One stacks up scores into bars; the other plots scores as points