Exam 5: Measures of Dispersion

If you calculated the standard deviation for a distribution of 20 scores,removed the 5 highest scores and recalculated,the value of the standard deviation would

Since computation of the standard deviation requires addition,division,and other mathematical operations,it should be used for

The scores below are from the same final exam given in a math class in two different years.Compute the mean and median (if necessary)and the range and standard deviation of these scores.Using these statistics,describe the differences in the two sets of scores. $\underline { \text { This year } }$ 35 45 65 75 80 69 71 53 99 95 70 82 93 67 61 57 72 77 71 81 $\underline { \text { Ten years' } }$ $\underline { \text { ago } }$ 56 77 75 76 74 51 89 55 67 77 69 90 90 65 79 69 87 86 98 91

The second quartile (Q₂)is equal in value to

One problem with the range (R)as a measure of dispersion is that it

Measures of dispersion provide information about the

Four students have applied to a special program and only one can be accepted.They have taken a battery of 12 tests and all have exactly the same average score.The standard deviation of their test scores are: Student A = 3.12,Student B = 0.27,Student C = 13.45,Student D = 6.45.If consistency of performance is a criteria for acceptance,which of the four students should be selected?

If a test score lies at the first quartile,it is

Your score on the test is the same as the third quartile (Q₃).You may conclude that

If a variable is interval-ratio in level of measurement,the preferred measure of dispersion would be

A "good" measure of dispersion should

If male and female college students have the same mean GPA but the standard deviation for females is much larger,you may conclude that

Measures of dispersion indicate the degree to which a set of scores is

An advantage of the interquartile range (Q)over the range (R)is that it

If a distribution of scores has a mean of 30 and a range of 0,

As a distribution of scores becomes more variable,the value of the standard deviation

If both male and female college students work an average of 15 hours per week during the school year and the standard deviation is 5.4 for male students and 2.3 for female students,what may we conclude?

The average deviation is based on

If the variance of a distribution is 16,the mean is 12,and the number of cases is 24,the standard deviation is