Ch 4-7 Review

Definitions

100

The average of a sample or population.

What is the mean?

200

Half of the scores are above this value, the other half are below.

What is the median?

300

A measure of deviation from the mean of a data set.

What is Sum of Squares

400

A continuous probability distribution with a mean of 0 and a standard deviation of 1.

What is the z-curve?

500

A term that describes when variability in X equals the variability in Y.

What is homoscedasticity?

Variables

100

μ

What is population mean?

200

s

What is sample standard deviation?

300

Σx²

What is the sum of squared x-values?

400

d-hat

What is Cohen's D?

500

ρ

What is Spearman's rho?

Formulas

100

The formula for obtaining a z-score.

z = (x-μ)/σ

200

The formula for standard deviation.

s=sqrt(SS/N-1)

300

The formula for Pearson's R.

r=SCP/Sqrt(SSxSSy)

400

The formula for the Sum of Cross Product Deviations.

Σ(xy)-(Σ(x)Σ(y))/N

500

The formula for the Standard Error of the Estimate.

Sqrt([SSy-((SCP)^2/SSx)]/N-2)

Conceptual Questions

100

This value can range from -1 to 1.

What is Pearson's r?

200

The reason why not every data point will fall on our regression line.

What is error?

300

The variability in y accounted for by x.

What is r^2?

400

How many standard deviations from the mean of a z-distribution is a z-score of 2.3?

What is 2.3 standard deviations?

500

The conceptual formula for variability of a data set.

Yact-Ymean=(Ypred-Ymean)+(Yact-Ypred)