Question 1

An appropriate measure of central tendency for ordinal data is the mode.

Accepted Answer

A) True 
 B)False

Question 2

A given set of normally distributed data values has a mean of 75, a standard deviation of 8.50 and a z-score of -2.45.What is the approximate value of x1?

Accepted Answer

A) 20.82 
B) 51.00 
C) 54.18 
D) 95.85 
E) 83.82 
A) 20.82 
B) 51.00 
C) 54.18 
D) 95.85 
E) 83.82

Question 3

A z score value between -1.00 and +1.00 represent approximately 68% of the values in a given data set.

Accepted Answer

A) True 
 B)False

Question 4

The following twelve data values are provided:   The 80th percentile is _____

Accepted Answer

A) 187 
B) 244 
C) 302 
D) 440 
E) 578 
A) 187 
B) 244 
C) 302 
D) 440 
E) 578

Question 5

A statistics student made the following grades on the first 6 tests: 76, 82, 92, 95, 92, 86.The total number of tests for the semester is 7.If the median score for the whole semester was 92, what could not have been the score of the last test?

Accepted Answer

A) 77 
B) 92 
C) 93 
D) 94 
E) 96 
A) 77 
B) 92 
C) 93 
D) 94 
E) 96

Question 6

The most appropriate measure of central tendency for nominal-level data is the median.

Accepted Answer

A) True 
 B)False

Question 7

A company is reviewing the database of customer purchases over the past 3 years.Using descriptive statistics on this large data set, a business analyst found the following values.   From this we can conclude that,

Accepted Answer

A) 95% of these purchases are between $105.24 and $74.88 
B) The distribution of these purchases is negatively skewed 
C) More of these purchases had values less than $74.88 than above that amount 
D) The distribution of these purchases is positively skewed 
E) The distribution of these purchases is not skewed 
A) 95% of these purchases are between $105.24 and $74.88 
B) The distribution of these purchases is negatively skewed 
C) More of these purchases had values less than $74.88 than above that amount 
D) The distribution of these purchases is positively skewed 
E) The distribution of these purchases is not skewed

Question 8

In a large data set, an analyst finds that the interquartile range is 102 to 331, indicating that about 75% of the data points fall within that range.

Accepted Answer

A) True 
 B)False

Question 9

The mean of Q3 and Q2 is the same as the median.

Accepted Answer

A) True 
 B)False

Question 10

If a large data set can be assumed to be normally distributed, then a business analyst could apply the normality rule to determine a range with approximately 60% of the data.

Accepted Answer

A) True 
 B)False

Question 11

According to Chebyshev's Theorem, how many values in a data set will be within two standard deviations of the mean?

Accepted Answer

A) at least 75% 
B) at least 68% 
C) at least 95% 
D) at least 89% 
E) at least 99% 
A) at least 75% 
B) at least 68% 
C) at least 95% 
D) at least 89% 
E) at least 99%

Question 12

A measure of how peaked the data is, is called kurtosis.

Accepted Answer

A) True 
 B)False

Question 13

If the mean, median, and mode are equal, then the distribution is positively skewed.

Accepted Answer

A) True 
 B)False

Question 14

According to Chebyshev's Theorem, how many values in a data set will be within three standard deviations of the mean?

Accepted Answer

A) at least 75% 
B) at least 68% 
C) at least 95% 
D) at least 89% 
E) at least 99% 
A) at least 75% 
B) at least 68% 
C) at least 95% 
D) at least 89% 
E) at least 99%

Question 15

The empirical rule says that approximately what percentage of the values would be within one standard deviation of the mean in a bell shaped set of data?

Accepted Answer

A) 95% 
B) 68% 
C) 50% 
D) 97.7% 
E) 100% 
A) 95% 
B) 68% 
C) 50% 
D) 97.7% 
E) 100%

Question 16

David Desreumaux, VP of Human Resources of Maritime Boat Manufacturing (MBM), is reviewing the employee training programs of MBM factories.His staff reports several statistics for safety training hours.The mean is 20 hours, the standard deviation is 5 hours, the median is 15 hours, and mode is 10 hours.The Pearsonian coefficient of skewness for safety training hours is ___.

Accepted Answer

A) 6 
B) 1 
C) 3 
D) 4 
E) 0 
A) 6 
B) 1 
C) 3 
D) 4 
E) 0

Question 17

The hourly production of a plastic cup company is tracked over the most recent several months and is found to be normally distributed.Comparing the mean of this data set to a similar data set collected last year during the same months, the business analyst notices that the mean has increased, while the overall shape of the distribution has not.Which of the following would not be a possible explanation for this difference?

Accepted Answer

A) the overall distribution has shifted to the right 
B) one or two large outliers occurred in the more recent data set 
C) the mode increased as well 
D) one or two small outliers occurred in the earlier data set 
E) the overall distribution has shifted to the left 
A) the overall distribution has shifted to the right 
B) one or two large outliers occurred in the more recent data set 
C) the mode increased as well 
D) one or two small outliers occurred in the earlier data set 
E) the overall distribution has shifted to the left

Question 18

Considering sales levels at each hour of operation in a shoe store over the past year, a business analyst looks at a histogram that has the selling hours of the day along the horizontal axis and the frequency of sales along the vertical axis.The analyst notices that the distribution is left skewed.From this, the analyst could conclude that ___________

Accepted Answer

A) most sales are made later in the day 
B) sales are made evenly throughout the day 
C) the store should close earlier in the day due to lack of sales at that time 
D) most sales are made earlier in the day 
E) most sales are made in the middle of the day 
A) most sales are made later in the day 
B) sales are made evenly throughout the day 
C) the store should close earlier in the day due to lack of sales at that time 
D) most sales are made earlier in the day 
E) most sales are made in the middle of the day

Question 19

A commuter travels many kilometres to work each morning.She has timed this trip 5 times during the last month.The time (in minutes)required to make this trip was 34, 39, 41, 35, and 41.The median time (in minutes)required for this trip was ___.

Accepted Answer

A) 39 
B) 41 
C) 37.5 
D) 38 
E) 35.5 
A) 39 
B) 41 
C) 37.5 
D) 38 
E) 35.5

Question 20

The lowest appropriate level of measurement for the median is ordinal.

Accepted Answer

A) True 
 B)False

An appropriate measure of central tendency for ordinal data is the mode.

A given set of normally distributed data values has a mean of 75, a standard deviation of 8.50 and a z-score of -2.45.What is the approximate value of x₁?

A z score value between -1.00 and +1.00 represent approximately 68% of the values in a given data set.

The following twelve data values are provided: The 80^th percentile is _____

A statistics student made the following grades on the first 6 tests: 76, 82, 92, 95, 92, 86.The total number of tests for the semester is 7.If the median score for the whole semester was 92, what could not have been the score of the last test?

The most appropriate measure of central tendency for nominal-level data is the median.

A company is reviewing the database of customer purchases over the past 3 years.Using descriptive statistics on this large data set, a business analyst found the following values. From this we can conclude that,

In a large data set, an analyst finds that the interquartile range is 102 to 331, indicating that about 75% of the data points fall within that range.

The mean of Q₃and Q₂ is the same as the median.

If a large data set can be assumed to be normally distributed, then a business analyst could apply the normality rule to determine a range with approximately 60% of the data.

According to Chebyshev's Theorem, how many values in a data set will be within two standard deviations of the mean?

A measure of how peaked the data is, is called kurtosis.

If the mean, median, and mode are equal, then the distribution is positively skewed.

According to Chebyshev's Theorem, how many values in a data set will be within three standard deviations of the mean?

The empirical rule says that approximately what percentage of the values would be within one standard deviation of the mean in a bell shaped set of data?

A commuter travels many kilometres to work each morning.She has timed this trip 5 times during the last month.The time (in minutes)required to make this trip was 34, 39, 41, 35, and 41.The median time (in minutes)required for this trip was ___.

The lowest appropriate level of measurement for the median is ordinal.

Introduction to Statistics

Charts and Graphs

Probability

Discrete Distributions

Continuous Distributions

Sampling and Sampling Distributions

Statistical Inference: Estimation for Single Populations

Statistical Inference: Hypothesis Testing for Single Populations

Statistical Inferences About Two Populations

Analysis of Variance and Design of Experiments

Simple Regression Analysis and Correlation

Multiple Regression Analysis

Building Multiple Regression Models

Time-Series Forecasting and Index Numbers

Analysis of Categorical Data

Nonparametric Statistics

Statistical Quality Control

Decision Analysis

Filters

Exam 3: Descriptive Statistics

An appropriate measure of central tendency for ordinal data is the mode.

A given set of normally distributed data values has a mean of 75, a standard deviation of 8.50 and a z-score of -2.45.What is the approximate value of x1?

A z score value between -1.00 and +1.00 represent approximately 68% of the values in a given data set.

The following twelve data values are provided: The 80th percentile is _____

A statistics student made the following grades on the first 6 tests: 76, 82, 92, 95, 92, 86.The total number of tests for the semester is 7.If the median score for the whole semester was 92, what could not have been the score of the last test?

The most appropriate measure of central tendency for nominal-level data is the median.

A company is reviewing the database of customer purchases over the past 3 years.Using descriptive statistics on this large data set, a business analyst found the following values. From this we can conclude that,

In a large data set, an analyst finds that the interquartile range is 102 to 331, indicating that about 75% of the data points fall within that range.

The mean of Q3 and Q2 is the same as the median.

If a large data set can be assumed to be normally distributed, then a business analyst could apply the normality rule to determine a range with approximately 60% of the data.

According to Chebyshev's Theorem, how many values in a data set will be within two standard deviations of the mean?

A measure of how peaked the data is, is called kurtosis.

If the mean, median, and mode are equal, then the distribution is positively skewed.

According to Chebyshev's Theorem, how many values in a data set will be within three standard deviations of the mean?

The empirical rule says that approximately what percentage of the values would be within one standard deviation of the mean in a bell shaped set of data?

A commuter travels many kilometres to work each morning.She has timed this trip 5 times during the last month.The time (in minutes)required to make this trip was 34, 39, 41, 35, and 41.The median time (in minutes)required for this trip was ___.

The lowest appropriate level of measurement for the median is ordinal.

Introduction to Statistics

Charts and Graphs

Probability

Discrete Distributions

Continuous Distributions

Sampling and Sampling Distributions

Statistical Inference: Estimation for Single Populations

Statistical Inference: Hypothesis Testing for Single Populations

Statistical Inferences About Two Populations

Analysis of Variance and Design of Experiments

Simple Regression Analysis and Correlation

Multiple Regression Analysis

Building Multiple Regression Models

Time-Series Forecasting and Index Numbers

Analysis of Categorical Data

Nonparametric Statistics

Statistical Quality Control

Decision Analysis

Filters

A given set of normally distributed data values has a mean of 75, a standard deviation of 8.50 and a z-score of -2.45.What is the approximate value of x₁?

The following twelve data values are provided: The 80^th percentile is _____

The mean of Q₃and Q₂ is the same as the median.