Quiz 7

the value of pearson's r ranges between

-1.0 and 1.0

you find a correlation between creativity and academic honesty of r= -.40. the coefficient of determination for this relationship is

.16 r^2

the closer the absolute value of a Pearson's r is to the absolute value of ____, the stronger the relationship between 2 variables

1.0

after computing a correlation, we compare our computed r value to the critical values for Pearson's r using ____ degrees of freedom

N-2

after a study that assessed the anxiety of students before a research methods test, the researcher reports that all the students scored between 20 and 25 on the 25pt scale of anxiety. what problem might exist with the scale

ceiling effect

the statistic describes the proportion of variability that is accounted for by knowing the relationship between 2 variables is the

coefficient of determination

the point-biserial correlation coefficient (rpb) is used to analyze the

correlation between a dichotomous and an interval/ratio variable

the more scattered the points on a scatterplot, the stronger the relationship between the variables (T/F)

false

we want our computed r value to be ____ the critical value listed in the table in order for it to be significant

greater than

the strength of the relationship is evident from _____ and the direction of the relationship is evident from ____ in a correlation coefficient

how close the correlation coefficient is to the absolute value of 1.0; the sign of the coefficient

when 2 variables move in opposite directions (one increases as the other decreases), they are

negatively correlated

____ is a measure of the strength of a linear association between 2 variables and is denoted by r

pearson correlation

you want to examine the relationship between owning a house (yes-no) and income. you would compute a

point-biserial correlation coeffienct

which has a stronger correlation: r=+.35 or r= -.50

r= -.50 because it's closer to 1 (positive and negative doesn't matter in this case)

a correlation coefficient provides 2 pieces of information about a relationship. they are the

strength and direction of a relationshp

you believe that students' anxiety is related to test scores in research methods. which of the following represents a directional alternative hypothesis for your study

students' anxiety will be negatively related to their test scores in research methods

a correlation of -.52 represents a stronger relationship than a correlation of .35 (T/F)

true

correlational designs are sometimes used when variables can't ethically or feasibly be manipulated (T/F)

true

one of the reasons why correlation doesn't equal causation is because there is the possibility that a third variable is responsible for the relationship (T/F)

true