The numerical value of the variance

The numerical value of the variance

a. is always larger than the numerical value of the standard deviation
b. is always smaller than the numerical value of the standard deviation
c. is negative if the mean is negative
d. can be larger or smaller than the numerical value of the standard deviation


Answer: d. can be larger or smaller than the numerical value of the standard deviation

The coefficient of correlation

The coefficient of correlation

a. is the same as the coefficient of determination
b. can be larger than 1
c. cannot be larger than 1
d. cannot be negative


Answer: c. cannot be larger than 1

The coefficient of correlation ranges between

The coefficient of correlation ranges between

a. 0 and 1
b. -1 and +1
c. minus infinity and plus infinity
d. 1 and 100


Answer: b. -1 and +1

A numerical measure of linear association between two variables is the

A numerical measure of linear association between two variables is the

a. variance
b. coefficient of variation
c. correlation coefficient
d. standard deviation


Answer: c. correlation coefficient

Positive values of covariance indicate

Positive values of covariance indicate

a. a positive variance of the x values
b. a positive variance of the y values
c. the standard deviation is positive
d. positive relation between the independent and the dependent variables


Answer: d. positive relation between the independent and the dependent variables

A numerical measure of linear association between two variables is the

A numerical measure of linear association between two variables is the

a. variance
b. covariance
c. standard deviation
d. coefficient of variation


Answer: b. covariance

The measure of dispersion which is not measured in the same units as the original data is the

The measure of dispersion which is not measured in the same units as the original data is the

a. median
b. standard deviation
c. coefficient of determination
d. variance


Answer: d. variance

The variance of the sample

The variance of the sample

a. can never be negative
b. can be negative
c. cannot be zero
d. cannot be less than one


Answer: a. can never be negative

The symbol σ2 is used to represent

The symbol σ2 is used to represent

a. the variance of the population
b. the standard deviation of the sample
c. the standard deviation of the population
d. the variance of the sample


Answer: a. the variance of the population

The symbol σ is used to represent

The symbol σ is used to represent

a. the variance of the population
b. the standard deviation of the sample
c. the standard deviation of the population
d. the variance of the sample


Answer: c. the standard deviation of the population

Which of the following symbols represents the size of the sample

Which of the following symbols represents the size of the sample

a. σ2
b. σ
c. N
d. n


Answer: d. n

Which of the following symbols represents the size of the population?

Which of the following symbols represents the size of the population?

a. σ2
b. σ
c. μ
d. N


Answer: d. N

The sum of deviations of the individual data elements from their mean is

The sum of deviations of the individual data elements from their mean is

a. always greater than zero
b. always less than zero
c. sometimes greater than and sometimes less than zero, depending on the data elements
d. always equal to zero


Answer: d. always equal to zero

The variance can never be

The variance can never be

a. zero
b. larger than the standard deviation
c. negative
d. smaller than the standard deviation


Answer: c. negative

The coefficient of variation is

The coefficient of variation is

a. the same as the variance
b. the standard deviation divided by the mean times 100
c. the square of the standard deviation
d. the mean divided by the standard deviation


Answer: b. the standard deviation divided by the mean times 100

The sample variance

The sample variance

a. is always smaller than the true value of the population variance
b. is always larger than the true value of the population variance
c. could be smaller, equal to, or larger than the true value of the population variance
d. can never be zero


Answer: c. could be smaller, equal to, or larger than the true value of the population variance

The numerical value of the standard deviation can never be

The numerical value of the standard deviation can never be

a. larger than the variance
b. zero
c. negative
d. smaller than the variance


Answer: c. negative

The descriptive measure of dispersion that is based on the concept of a deviation about the mean is

The descriptive measure of dispersion that is based on the concept of a deviation about the mean is

a. the range
b. the interquartile range
c. the absolute value of the range
d. the standard deviation


Answer: d. the standard deviation

When should measures of location and dispersion be computed from grouped data rather than from individual data values?

When should measures of location and dispersion be computed from grouped data rather than from individual data values?

a. as much as possible since computations are easier
b. only when individual data values are unavailable
c. whenever computer packages for descriptive statistics are unavailable
d. only when the data are from a population


Answer: b. only when individual data values are unavailable

The measure of dispersion that is influenced most by extreme values is

The measure of dispersion that is influenced most by extreme values is

a. the variance
b. the standard deviation
c. the range
d. the interquartile range


Answer: c. the range