Research Methods Quiz 12

Which of the following is true of standard deviation?

It becomes larger as more people have scores that lie farther from the mean value.

Which of the following statements is true regarding nominal scales?

The levels of these scale variables are simply different categories or groups.

Craig examines the effect of different genres of music, such as jazz, rock, and rap, on task performance. Which type of measurement scale do the genres of music represent?

a nominal scale

Which of the following scales of measurement lacks numerical properties?

a nominal scale

Which of the following examples best represents the use of an interval scale?

assessing students' ratings of their professors' performance on a five-point scale ranging from poor to excellent

When graphing frequency distributions, ________ are most commonly used to depict simple descriptions of categories for a single variable.

bar graphs

A teacher displays her students' test grades on a notice board. According to the results, 7 students received the grade of A, 10 students received the grade of B, 18 students received the grade of C, 4 students received the grade of D, and 1 student received the grade of E. In statistical terms, this is a

frequency distribution

The standard deviation is appropriate only for

interval and ratio scale variables.

The Pearson r correlation coefficient is appropriate for use when both variables have

interval or ratio scale properties.

The ________ of a set of scores is obtained by adding all the scores and dividing by the number of scores.

mean

Variables with ________ scale levels exhibit minimal quantitative distinctions.

ordinal

The Pearson product-moment correlation coefficient

provides information about the strength of a relationship between variables.

Samira took an aptitude test when applying for a position with Accountants Unlimited. She was hired the following week. In this scenario, the predictor variable is Samira's

score on the aptitude test.

A teacher displays the results of a test on a notice board. According to the results, half the students had scored more than 70% on the test. Which measure of central tendency does this scenario exemplify?

the median

Workers at an automobile repair shop report that half of the automobiles they repair have a resale value below $8,000. Which measure of central tendency is exemplified in this scenario?

the median

When describing relationships between variables, a Pearson r correlation of 0.00 indicates that

there is no relationship between the variables.

The general form of a regression equation is

Y = a + bX.

A researcher measures the time taken by participants to press a button following a signal. This measure is an example of a(n) ________ scale.

ratio

When describing relationships between variables, a Pearson r correlation nearer to 1.00 (plus or minus) indicates that

the relationship between the variables is strong.

A correlation coefficient is used

to describe the strength of the relationship between two variables.