Exam I Review (Thu)

Question 1

One can use multiple survey items to measure a construct to increase the __ of the measurement.

Accepted Answer

reliability

Question 2

Which of the following is NOT a characteristic of the normal probability distribution?

Accepted Answer

The standard deviation must be 1

Question 3

Gender is an example of the ...

Accepted Answer

nominal scale

Question 4

Mean age of 20 LER students is 22. One can conclude that mean age of all LER students ...

Accepted Answer

could be larger, smaller, or equal to 22

Question 5

Exponential probability distribution is a type of discrete probability distribution.

Accepted Answer

False

Question 6

Social security number is an example of ...

Accepted Answer

a categorical variable

Question 7

The center of a normal curve is ...

Accepted Answer

is the mean of the distribution

Question 8

The shape of a normal distribution is determined by its mean and standard deviation only.

Accepted Answer

True

Question 9

The distribution of students' scores on a VERY easy exam is likely to be positively skewed.

Accepted Answer

False

Question 10

When data are negatively skewed, the mean will usually be ...

Accepted Answer

smaller than the median

Question 11

The numerical value of the standard deviation can never be ...

Accepted Answer

negative

Question 12

The total area under a continuous probability distribution curve always equals 1.

Accepted Answer

True

Question 13

A sample of 5 scores has a mean of 4. A score of 10 is added to the sample. The new mean is ..

Accepted Answer

5

Question 14

The measure of variability that is influenced most by extreme values is ...

Accepted Answer

range

Question 15

The symbol σ is used to represent ...

Accepted Answer

the standard deviation of the population

Question 16

The ordinal scale of measurement has the properties of the ...

Accepted Answer

nominal scale

Question 17

The variance of a sample of 169 observations equals 576. The sd of the sample equals ...

Accepted Answer

24

Question 18

Under a normal distribution, about how many values are within the +1/-1 SD from the mean?

Accepted Answer

68%

Question 19

For a continuous variable, the probability that the variable takes on a specific value is ...

Accepted Answer

almost zero

Question 20

Income is an example of a variable that uses the ...

Accepted Answer

ratio scale

Question 21

In a standard normal distribution, the probability that Z is greater than zero is ...

Accepted Answer

0.5

Question 22

The best way to draw cause-and-effect reference between two variables is experimental method.

Accepted Answer

True

Question 23

Z-transformation can transform any distribution to a normal distribution.

Accepted Answer

False

Question 24

For any normal distribution, its mean, mode, and median have the exactly same value.

Accepted Answer

True

Question 25

Larger values of SD results in a normal distribution curve to be wider and flatter.

Accepted Answer

True

Question 26

"Since 20% UIUC students are business major, 20% of all US college students are business major"

Accepted Answer

is an example of statistical inference

Question 27

The uniform, normal, and exponential distributions are ...

Accepted Answer

all continuous probability distributions

Question 28

A population has μ = 50 and σ = 5. What is the new μ if each score is multiplied by 2?

Accepted Answer

100

Question 29

A reliable scale is always valid.

Accepted Answer

False

Exam I Review (Thu)

Questions 29

Exam I Review (Thu)

Questions 29