Question 1

NARRBEGIN: Weights of Teachers
Weights of Teachers
The following data represent the weights in pounds of a sample of 25 teachers: 164, 148, 137, 157, 173, 156, 177, 172, 169, 165, 145, 168, 163, 162, 174, 152, 156, 168, 154, 151, 174, 146, 134, 140, and 171.NARREND
-{Weights of Teachers Narrative} Compute the sample variance, and sample standard deviation.

Accepted Answer

The answer of NARRBEGIN: Weights of Teachers
Weights of Teachers
The following...

Question 2

NARRBEGIN: Weights of Teachers
Weights of Teachers
The following data represent the weights in pounds of a sample of 25 teachers: 164, 148, 137, 157, 173, 156, 177, 172, 169, 165, 145, 168, 163, 162, 174, 152, 156, 168, 154, 151, 174, 146, 134, 140, and 171.NARREND
-{Weights of Teachers Narrative} Compute the range and coefficient of variation.

Accepted Answer

The answer of NARRBEGIN: Weights of Teachers
Weights of Teachers
The following...

Question 3

Is a standard deviation of 10 a large number indicating great variability, or is it small number indicating little variability? To answer this question correctly, one should look carefully at the value of the:
A)mean.
B)standard deviation.
C)coefficient of variation.
D)mean dividing by the standard deviation.

Accepted Answer

The coefficient of variation (C) is the correct answer because it is a measure that indicates the extent of variability in relation to the mean of the population. It is calculated as the ratio of the standard deviation to the mean, and it provides a standardized measure of dispersion of a probability distribution or frequency distribution. This is useful for comparing the degree of variation from one data series to another, even if the means are drastically different from each other.

Question 4

According to the Empirical Rule, if the data form a bell shaped normal distribution, approximately ____________________ percent of the observations will be contained within 2 standard deviations around the mean.

Accepted Answer

The answer of According to the Empirical Rule, if the...

Question 5

The following data represent the number of children in a sample of 10 families from a certain community: 4, 2, 1, 1, 5, 3, 0, 1, 0, and 2.
a.Compute the range.
b.Compute the variance.
c.Compute the standard deviation.
d.Compute the coefficient of variation.
e.Explain why in this case range > variance > standard deviation > coefficient of variation.

Accepted Answer

The answer of The following data represent the number of...

Question 6

The ____________________ is the square root of the ____________________.

Accepted Answer

The answer of The ____________________ is the square root of...

Question 7

Which of the following is a measure of variability?
A)The interquartile range
B)The variance
C)The coefficient of variation
D)All of these choices are true.

Accepted Answer

All of these choices (interquartile range, variance, and coefficient of variation) are measures of variability. The interquartile range measures the spread of the middle 50% of the data, the variance measures how far each value is from the mean, and the coefficient of variation measures the relative amount of variability in relation to the mean.

Question 8

According to the Empirical Rule, if the data form a bell shaped normal distribution approximately ____________________ percent of the observations will be contained within 1 standard deviation around the mean.

Accepted Answer

The answer of According to the Empirical Rule, if the...

Question 9

The ____________________ is the least effective of all the measures of variability.

Accepted Answer

The answer of The ____________________ is the least effective of...

Question 10

____________________ uses both the mean and the standard deviation to interpret standard deviation for histograms of any shape.

Accepted Answer

The answer of ____________________ uses both the mean and the...

Question 11

The ____________________ uses both the mean and the standard deviation to interpret standard deviation for bell shaped histograms.

Accepted Answer

The answer of The ____________________ uses both the mean and...

Question 12

Which of the following statements is true regarding the data set 8, 8, 8, 8, and 8?
A)The range equals 0.
B)The standard deviation equals 0.
C)The coefficient of variation equals 0.
D)All of these choices are true.

Accepted Answer

- Option A is true because the range is the difference between the highest and the lowest value in a data set. In this case, all the values are the same, so the range is 0.
- Option B is true because the standard deviation is a measure of how much the values deviate from the mean. Since all the values are the same and equal to the mean, there is no deviation and the standard deviation is 0.
- Option C is true because the coefficient of variation is the ratio of the standard deviation to the mean, expressed as a percentage. Since the standard deviation is 0 and the mean is a non-zero value, the coefficient of variation is 0.

Question 13

The range, variance, standard deviation, and coefficient of variation are to be used only on ____________________ data.

Accepted Answer

The answer of The range, variance, standard deviation, and coefficient...

Question 14

There are three statistics used to measure variability in a data set; the range, the ____________________ and the ____________________.

Accepted Answer

The answer of There are three statistics used to measure...

Question 15

Chebysheff's Theorem states that the percentage of measurements in a data set that fall within three standard deviations of their mean is:
A)75%.
B)at least 75%.
C)89%.
D)at least 89%.

Accepted Answer

Chebysheff's Theorem states that for any data set, regardless of distribution, at least 1 - (1/k^2) of the data falls within k standard deviations from the mean. For k=3, this is at least 1 - (1/9) = 89%.

Question 16

Which of the following types of data has no measure of variability?
A)Interval data
B)Nominal data
C)Bimodal data
D)None of these choices.

Accepted Answer

Nominal data refers to categorical data where each category is distinct and there is no inherent order or ranking. As there is no numerical value assigned to the categories, there is no measure of variability. Interval data, on the other hand, has a measure of variability in the form of standard deviation, range, etc. Bimodal data is a type of distribution and not a type of data.

Question 17

A basketball player has the following points for seven games: 20, 25, 32, 18, 19, 22, and 30. Compute the following measures of variability.
a.Standard deviation
b.Coefficient of variation
c.Compare the standard deviation and coefficient of variation and use them to discuss the variability in the data.

Accepted Answer

The answer of A basketball player has the following points...

Question 18

According to the Empirical Rule, if the data form a bell shaped normal distribution approximately ____________________ percent of the observations will be contained within 3 standard deviations around the mean.

Accepted Answer

The answer of According to the Empirical Rule, if the...

Question 19

A statistic that interprets the standard deviation relative to the size of the numbers in the data set is called the ____________________ of ____________________.

Accepted Answer

The answer of A statistic that interprets the standard deviation...

Question 20

The smaller the spread of scores around the mean:
A)the smaller the variance of the data set.
B)the smaller the standard deviation of the data set.
C)the smaller the coefficient of variation of the data set.
D)All of these choices are true.

Accepted Answer

All of these statements are true because the spread of scores around the mean directly affects the variance, standard deviation, and coefficient of variation of a data set. A smaller spread indicates that the data points are closer to the mean, leading to a smaller variance and standard deviation. Since the coefficient of variation is a standardized measure of dispersion that takes into account the mean of the dataset, a smaller spread around the mean also results in a smaller coefficient of variation.

Quiz 4: Numerical Descriptive Techniques

Is a standard deviation of 10 a large number indicating great variability, or is it small number indicating little variability? To answer this question correctly, one should look carefully at the value of the:

According to the Empirical Rule, if the data form a bell shaped normal distribution, approximately ____________________ percent of the observations will be contained within 2 standard deviations around the mean.

The is the square root of the .

Which of the following is a measure of variability?

According to the Empirical Rule, if the data form a bell shaped normal distribution approximately ____________________ percent of the observations will be contained within 1 standard deviation around the mean.

The ____________________ is the least effective of all the measures of variability.

____________________ uses both the mean and the standard deviation to interpret standard deviation for histograms of any shape.

The ____________________ uses both the mean and the standard deviation to interpret standard deviation for bell shaped histograms.

Which of the following statements is true regarding the data set 8, 8, 8, 8, and 8?

The range, variance, standard deviation, and coefficient of variation are to be used only on ____________________ data.

There are three statistics used to measure variability in a data set; the range, the and the .

Chebysheff's Theorem states that the percentage of measurements in a data set that fall within three standard deviations of their mean is:

Which of the following types of data has no measure of variability?

According to the Empirical Rule, if the data form a bell shaped normal distribution approximately ____________________ percent of the observations will be contained within 3 standard deviations around the mean.

A statistic that interprets the standard deviation relative to the size of the numbers in the data set is called the of .

The smaller the spread of scores around the mean: