PSYCH 311: Exam 4

The correlation coefficient ranges between ________ and ________

-1; +1

If r = .25, then the coefficient of determination is ________________.

.0625

A researcher measures the following correlation: r = -.021. What is the value of the coefficient of determination? A) 0.04 B) -0.04 C) 0.42 D) -0.42

A - 0.04

If Chi^2 = 5.32 and n = 40, then what is the value of the coefficient of determination? A) 0.133 B) 0.36 C) 0.64 D) there is not enough information to answer this question

A - 0.133

A correlation of r = .38 in a sample of 30 participants is statistically significant for a two-tailed test at a .05 level of significance. A) true B) false

A - true

The coefficient of determination is mathematically equivalent to eta-squared. A) true B) false

A - true

Suppose a correlation is computed in each of two samples. If the value of SS(XY) is the same in each sample, and the square root of SS(X)SS(Y) is larger in Sample 1, the in which sample will the value of the correlation coefficient be larger? A) sample 1 B) sample 2 C) none; the correlation coefficient will be the same in both samples D) there is not enough information to answer this question

B - sample 2

The denominator of the correlation coefficient measures the extent to which two variables A) vary together B) vary independently C) covary D) both A and C

B - vary independently

The correlation coefficient ranges from -1.0 to +1.0, with values closer to ±1.0 indicating A) a more positive relationship between two factors B) a stronger relationship between two factors C) that two factors are less likely to be related D) that the correlation is due to outliers

B- a stronger relationship between two factors

A researcher measures the following correlation between number of years of education and life satisfaction: r = +0.08. What is the value of the coefficient of determination? A) 0.08 B) 0.16 C) 0.01 D) 0.11

C - 0.01

A researcher measures the relationship between two variables, X and Y. If SS(XY) = 340 and SS(X)SS(Y) = 320,000, then what is the value of the correlation coefficient? A) 0.32 B) 0.34 C) 0.60 D) almost a zero correlation

C - 0.60

A researcher measures the relationship between narcissism and willingness to help. If SS(XY) = 240, and SS(Y) = 410, then what is the value of the correlation coefficient? A) 0.002 B) 0.02 C) 0.66 D) 0.69

C - 0.66

A statistical procedure used to describe the strength and direction of the linear relationship between two factors is called A) effect size B) power C) a correlation D) coincidence

C - a correlation

The assumption that there is an equal variance or scatter of data points dispersed along the regression line is referred to as A) normality B) linearity C) homoscedasticity D) restriction of range

C - homoscedasticity

Which of the following indicated the strongest correlation? A) r = -0.57 B) r = +0.78 C) r = -0.90 D) r = +0.88

C - r = -0.90

The normality assumption states that the population of X and Y scores form a bivariate ("two valuable") normal distribution, such that A) the population of X and Y scores are normally distributed B) for each X score, the distribution of Y scores is normally distributed C) for each Y score, the distribution of X scores is normally distributed D) all the above

D - all the above

The numerator of the correlation coefficient measures the extent to which two variables A) vary together B) vary independently C) covary D) both A and C

D - both A and C

The correlation coefficient is used to measure the ______________ and ______________ of the linear relationship between two factors. A) date; time B) mean; variance C) significance; effect size D) strength; direction

D - strength; direction

The sign (+ or -) of a correlation coefficient indicates the ______________ of a relationship between two factors.

Direction

When finding the critical value in a chi-square distribution, how many tails do you look in for the cutoff?

One tail

The Spearman correlation coefficient is used to measure the correlation between two variables that are measured on a(n) _______________ scale.

Ordinal

The ________________ correlation coefficient is used to measure the correlation between two dichotomous variables.

Phi

The formula for the Spearman correlation coefficient was derived from the formula for ________________.

The Pearson correlation coefficient (Pearson r)

The most common measure of effect size for the correlation coefficient is called __________________.

The coefficient of determination