Statistics

RES 341 Quiz 2

Part I Select the correct answer and write or highlight the appropriate letter in the space provided

___a___ 1 . In a uniform distribution

a . the mean and the median are always equal

b . the mean and the standard deviation are always equal

c . the mean is always larger than the median

d . the mean is always smaller than the median

___d___ 2 . The normal distribution is

a . a bell-shaped distribution . b . a continuous distribution

c . symmetric . d . all of the above

___b___ 3 . The standard

normal distribution

a . is a special case of the normal distribution

b . has a mean equal to 0 and a standard deviation equal to 1

c . measures the distance from the mean in units of the standard deviation

d . all of the above

___c___ 4 . A normal distribution is completely described by

a . its mean . b . its standard deviation

c . its mean and standard deviation . d . of the above

___c___ 5 . Any normal distribution can be converted to a standard normal distribution by

a . finding n . b . determining that n ( is greater than 5

a . 68 . b . 34 . c . 95 . d . of the above

___d___ 7 A z value

a . is the standard deviation for the standard normal distribution

b . is a measure of how many standard deviations the mean is from the median

c . is the difference of the mean and the probability of z

d . is a measure of how many standard deviations a particular score is from the mean

___a___ 8 In a probability sample each item in the population has

a . a chance of being selected

b . the same chance of being selected

c . a 50 percent chance of being selected

d . no chance of being selected

__b____ 9 In a simple random sample each item in the population has

a . a chance of being selected

b . the same chance of being selected

c . a 50 percent chance of being selected

d . no chance of being selected

__a____ 10 The sampling error is

a . the difference between a sample statistic and a population parameter

b . always positive

c . the difference between the z value and the mean

d . equal to the population value

___a___11 The sample mean is an example of a

a . sample statistic

b . normal population

c . weighted mean

d . population parameter

___b___ 12 . In cluster sampling

a . each item in the population has a chance of being selected more than once

b . the population is divided into primary units , and then samples are drawn from these units

c . each item in a primary unit has a 50 percent chance of being selected

d . every k th item has a chance of being selected

___d___ 13 . In a systematic sample a random starting point is chosen and

a . each item in the population has a chance of being selected more than once

b . the population is divided into primary units , and then samples are drawn from these units

c . each item in a...