DESCRIPTIVE STATISTICS AND Z SCORES 7-15

7

A student took the Scholastic Aptitude Test (SAP) and obtained A student took the Scholastic Aptitude Test (SAP) and obtained the score 1260. The population average score for SAP is 1060 and the standard deviation is 100. It is known that there is a positive linear relationship between SAP and student's Grade Point Average (GPA). The correlation coefficient between these two variables is r = 0.6. The population GPA average is 3 and the standard deviation is 1.

What is the predicted student's GPA(raw score not standardized score)?

Select one:

a.4.2

b.4.6

c.3.9

d.5.2

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8

Which of the following is a measure of spread?

Select one:

a.Kurtosis

b.Median

c.IQR

d.Skewness

9

What is the sample variance of the five scores, 1, 0, 1, 1, and 2?

Select one:

a.50

b.0.5

c..025

d.0.5

10

Calculate the standard deviation of the following sample: 4, 6, 7, 7.

Select one:

a.1.999

b.1.414

c.1.225

d.2.000

11

A statistics student (Lee) wants to compare his final test score to his friend Zoey's final test score from last year. However, the two tests were scored on different scales. Lee asks Zoey for the mean and standard deviation of her class on the test as well as her final test score. Given these results, what are Lee and Zoey's Z-scores?

Lee: Final test score = 85; Class:M= 70;SD= 10

Zoey: Final test score = 45; Class:M= 35;SD= 5

Select one:

a.Lee,Z= 1.07; Zoey,Z= -1.14

b.Lee,Z= -1.07; Zoey,Z= -1.14

c.Lee,Z= 1.50; Zoey,Z= 2.00

d.Lee,Z= 1.07; Zoey,Z= 1.50

12

A psychologist is interested in studying self-aware and skeptical tendencies in people and develops measures of these two personality characteristics. Self-awareness and skepticism are__________ in the psychologist's research

Select one:

a.

Abstract concepts

b.

Values

c.Invariable constructs

d.

Variables

13

Jake'sZscore for running ability is 0.60. What is Jake's raw score (assumingMean=100 andSD= 7).

Select one:

a.

raw score = 93.5

b.raw score = 103.2

c.raw score = 104.2

d.raw score = 100.1

14

According to a standardised scoring system, a particular nation has a human

rights score of 41 which equals a Z score of 1.3. Assuming that nations' scores

have a normal distribution, what is the percentage of nations above this score?

Select one:

a.-9.68 %

b.9.68 %

c.99.68%

d.59.68%

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15

To draw conclusions about the population based on a sample the researcher should use

Select one:

a.Histogram

b.Descriptive statistics

c.SPSS

d.Inferential statistics