Question 1

When two variables, A and B, are strongly correlated, it means that
A) A has caused B
B) B has caused A
C) some third variable has caused both A and B to occur together
D) none of these

Accepted Answer

Correlation does not imply causation. A strong correlation between two variables means there is a strong relationship or association between them, but it does not specify that one variable causes the other or that they have a common cause.

Question 2

Of the following correlation coefficients, which expresses the strongest association?
A) .10
B) 0
C) -.50
D) -1.00

Accepted Answer

A correlation coefficient of -1.00 represents a perfect negative correlation, meaning that as one variable increases, the other variable decreases in a linear fashion. This is the strongest type of correlation possible.

Question 3

When two sets of measures have been found to be totally independent of each other, then the
A) correlation between them must be negative
B) correlation between them must be positive
C) correlation between them must be zero
D) no attempt to calculate the correlation should be made

Accepted Answer

If two sets of measures are independent of each other, it means that there is no relationship or association between them. Therefore, the correlation between them must be zero.

Question 4

The correlation coefficient, in and of itself,
A) never proves causation
B) never rules out causation
C) allows for better-than-chance predictions
D) all of these

Accepted Answer

The correlation coefficient only measures the strength and direction of a relationship between two variables, but it does not prove causation or rule out causation. Furthermore, the correlation coefficient can allow for better-than-chance predictions of one variable based on the other variable, but it does not guarantee accurate predictions. Therefore, choice D, all of these, is the best answer.

Question 5

The originator of the product-moment correlation technique was
A) Karl Gauss
B) Blaise Pascal
C) Karl Pearson
D) Alexandra McKenna

Accepted Answer

The product-moment correlation coefficient was developed by statisticians Francis Galton and Karl Pearson in the late 19th century. However, Pearson is often credited as the originator of the product-moment correlation technique as he extensively developed and popularized it in his work.

Question 6

Among elementary school children, the correlation between age and height would most probably be
A) positive
B) negative
C) zero
D) non-linear

Accepted Answer

It is most likely that as age increases, height will also increase, making the correlation positive. However, there may be individual differences and other factors that could affect the correlation, such as genetics and nutrition.

Question 7

The correlation between parental income and the amount of financial aid awarded by the college to students should most probably be
A) positive
B) negative
C) zero
D) none of these, since income is a nominal measure

Accepted Answer

The correlation between parental income and the amount of financial aid awarded by the college to students is typically negative, meaning that as parental income increases, the amount of financial aid awarded by the college decreases. This is because financial aid is often awarded to students who demonstrate financial need, which is typically lower for students with higher parental income.

Question 8

When the array of points on a scatter plot slopes from lower left to upper right, then
A) the correlation is positive
B) the correlation is negative
C) there is no correlation
D) no predictions can be made

Accepted Answer

When an array of points on a scatter plot slopes from lower left to upper right, it indicates a positive correlation between the variables being plotted. This means that as the value of one variable increases, the value of the other variable also increases. Therefore, the best choice is A.

Question 9

A scatter plot on which the array of points goes from upper left to lower right, indicates
A) a positive correlation
B) a negative correlation
C) a zero correlation
D) all of these, depending on the strength of the correlation

Accepted Answer

A scatter plot that shows points going from the upper left to the lower right indicates a negative correlation, meaning as one variable increases, the other decreases.

Question 10

Each data point on a scatter plot represents
A) the frequency of occurrence
B) a pair of scores
C) a score on one measurement
D) none of these

Accepted Answer

A scatter plot represents the relationship between two variables. Therefore, each data point on a scatter plot represents a pair of scores, one for each variable. Option A is incorrect as scatter plots do not represent frequency of occurrence. Option C is incorrect as scatter plots show the relationship between two measurements rather than a single score. Option D is incorrect as one of the options must be true.

Question 11

Negative correlations
A) may never be significant
B) may never be used for prediction
C) may never generalize to the population
D) none of these

Accepted Answer

None of these statements are true. Negative correlations can be significant, used for prediction, and can generalize to the population.

Question 12

On a scatter plot, the ordinate is used to represent
A) the scores on the Y measure
B) the scores on the X measure
C) the frequency of occurrence
D) the product moment

Accepted Answer

The ordinate, also known as the y-axis, is used to represent the scores or values of the Y measure in a scatter plot. The x-axis represents the scores or values of the X measure.

Question 13

The most common error in interpreting correlational research studies is in
A) assuming that the data have been incorrectly reported
B) assuming that the appropriate statistical analyses have been used
C) assuming that a causal factor has been isolated
D) all of these

Accepted Answer

Correlational studies do not establish causation, only a relationship between two variables. Assuming that a causal factor has been isolated is a common error in interpreting correlational research studies. The other options (A and B) may sometimes be a factor, but they are not as common as assuming causality.

Question 14

The more a correlation deviates from zero,
A) the more it is certain to be positive in sign
B) the more it is certain to be negative in sign
C) the more it is certain that the measured variables are independent of each other
D) the better its predictive accuracy

Accepted Answer

A correlation coefficient measures the strength and direction of a linear relationship between two variables. The closer the correlation coefficient is to -1 or 1, the stronger the relationship, thus improving predictive accuracy. Choices A, B, and C are incorrect because the sign (positive or negative) of the correlation indicates the direction of the relationship, not its strength or predictive accuracy, and a correlation deviating from zero does not imply variables are independent; in fact, it suggests they are related.

Question 15

The major reason for using the correlational techniques is to
A) make cause-and-effect statements
B) make better-than-chance predictions
C) identify a specific percentile
D) establish a significant difference

Accepted Answer

Correlational techniques are used to identify and measure the relationship between two variables. They allow us to make predictions about one variable based on the other variable. However, they do not establish cause-and-effect relationships, identify specific percentiles, or establish significant differences between groups. Therefore, the major reason for using correlational techniques is to make better-than-chance predictions.

Question 16

Of the following correlation coefficients, which expresses the weakest association?
A) .10
B) 0
C) -.50
D) -1.00

Accepted Answer

A correlation coefficient of 0 indicates no relationship between the two variables, whereas a correlation coefficient of .10 indicates a very weak relationship. Therefore, B expresses the weakest association.

Question 17

A "significant" correlation is one which
A) is especially meaningful
B) does not deviate from zero
C) indicates a valid difference
D) can be generalized to the population

Accepted Answer

A "significant" correlation means that the observed relationship is unlikely to have occurred by chance, and thus can be generalized to the population from which the sample was drawn.

Question 18

When variable A correlates highly with B, then
A) A has caused B
B) B has caused A
C) variable B correlates highly with A
D) none of these

Accepted Answer

Correlation between two variables means that as one variable changes, the other variable tends to change in a specific direction (either positively or negatively). However, correlation does not imply causation. Therefore, if variable A correlates highly with B, it also means that variable B correlates highly with A, as correlation is a mutual relationship.

Question 19

A maximum linear correlation is expressed as
A) 100%
B) 99
C) +10.00
D) +1.00

Accepted Answer

A maximum linear correlation is expressed as +1.00, which means a perfect positive correlation between two variables.

Question 20

In order to establish the significance of a correlation, one must know the value of the correlation coefficient and also
A) the number of paired scores
B) whether it relates to other measures
C) Whether it specifies the direction of the association
D) the sign of the correlation

Accepted Answer

The number of paired scores is essential to establish the significance of a correlation because it affects the degrees of freedom in statistical tests used to determine the significance of the correlation coefficient.

Quiz 11: The Hypothesis of Association: Correlation

When two variables, A and B, are strongly correlated, it means that

Of the following correlation coefficients, which expresses the strongest association?

When two sets of measures have been found to be totally independent of each other, then the

The correlation coefficient, in and of itself,

The originator of the product-moment correlation technique was

Among elementary school children, the correlation between age and height would most probably be

The correlation between parental income and the amount of financial aid awarded by the college to students should most probably be

When the array of points on a scatter plot slopes from lower left to upper right, then

A scatter plot on which the array of points goes from upper left to lower right, indicates

Each data point on a scatter plot represents

Negative correlations

On a scatter plot, the ordinate is used to represent

The most common error in interpreting correlational research studies is in

The more a correlation deviates from zero,

The major reason for using the correlational techniques is to

Of the following correlation coefficients, which expresses the weakest association?

A "significant" correlation is one which

When variable A correlates highly with B, then

A maximum linear correlation is expressed as

In order to establish the significance of a correlation, one must know the value of the correlation coefficient and also