Quiz 9

Correlation (linear) Regression

1. Which of the following are the correct hypotheses for testing linear correlations?

a) H0: μ = 0 H1: μ ≠ 0

b) H0: = 1 H1: ≠ 1

c) H0: = 0 H1: ≠ 0

d) H0: = H1: ≠

2. The diagram at bottom illustrates which type of relationship?

a) positive linearb) negative linearc) curvilineard) no relationship

Y

X

Y

X

3. What are the critical r-values for a two-tailed test of linear correlation for 12 pairs of data with =0.05?

a) +/–0.648b) +/–0.576c) +/–0.553d) +/–0.532

4. Twelve subjects were tested before and after an experimental treatment. Given a correlation of 0.740 is there a sig. linear correlation given =0.05?

a) yesb) noc) indeterminate

5. Given a correlation coefficient of 0.740 what is the coefficient of determination (amount of explained variation)?

a) 1.480 b) 0.548c) 0.452d) 0.860

6. What condition is necessary before determining a regression line?

a) data are approximately normally distributedb) slope is greater than 1.000c) mean difference is significantd) there is a significant correlation

7. The following regression equation was computed between body MASS and STRENGTH. Given a body mass of 70 kg what is the predicted strength in newtons?

a) 2170 Nb) 700 Nc) 206 Nd) 238 N

Coefficientsa

-31.582 35.494 -.890 .424

3.396 .474 .963 7.167 .002

(Constant)

MASS

Model1

B Std. Error

UnstandardizedCoefficients

Beta

StandardizedCoefficients

t Sig.

Dependent Variable: STRENGTHa.

8. Given the following SPSS output what can you conclude about the relationship?

a) no sig. linearb) sig. positive linearc) sig. negative lineard) sig. curvilinear Correlations

1 .873*

. .023

6 6

.873* 1

.023 .

6 6

Pearson Correlation

Sig. (2-tailed)

N

Pearson Correlation

Sig. (2-tailed)

N

IQFEMALE

IQMALE

IQFEMALE IQMALE

Correlation is significant at the 0.05 level (2-tailed).*.