Question 1

Calculate   for the following sample data set: ​   ​

Accepted Answer

A)  11.63 
B)  15.1 
C)  15.5 
D)  9 
A)  11.63 
B)  15.1 
C)  15.5 
D)  9

Question 2

The IQ curve is normal, with a mean of 100 and a standard deviation of 15.If "normal" IQ is defined as a score within 1 standard deviation of the mean, what range of scores is considered "normal"?

Accepted Answer

A)  85-115 
B)  75-125 
C)  100-115 
D)  85-100 
A)  85-115 
B)  75-125 
C)  100-115 
D)  85-100

Question 3

If we have a distribution with ith deviation from the mean equal to 0, then we know that:

Accepted Answer

A)  the distribution is symmetric. 
B)  the ith observation is the same as the mean. 
C)  the variance must be 0. 
D)  the median would be a more accurate representation of central tendency. 
A)  the distribution is symmetric. 
B)  the ith observation is the same as the mean. 
C)  the variance must be 0. 
D)  the median would be a more accurate representation of central tendency.

Question 4

A personnel manager believes that a particular employee produces more defective parts than his peers.The manager records the worker's production over the course of several weeks.Out of 315 parts produced, 11 are defective.Calculate   (the sample proportion) if we define a defective part as a "success."

Accepted Answer

A)  0.035 
B)  11 
C)  28.64 
D)  Need more information 
A)  0.035 
B)  11 
C)  28.64 
D)  Need more information

Question 5

It is known that the body mass index (BMI) of healthy American females follows a normal distribution, with a mean of 22.5 and a standard deviation pf 3.0.Approximately what percentage of female BMI values fall between 16.5 and 28.5?

Accepted Answer

A)  99.7% 
B)  95% 
C)  81.5% 
D)  68% 
A)  99.7% 
B)  95% 
C)  81.5% 
D)  68%

Question 6

σ is the symbol for the:

Accepted Answer

A)  sample standard deviation. 
B)  population standard deviation. 
C)  population variance. 
D)  squared sample standard deviation. 
A)  sample standard deviation. 
B)  population standard deviation. 
C)  population variance. 
D)  squared sample standard deviation.

Question 7

What is the largest possible value of the sample standard deviation?

Accepted Answer

A)  100 
B)  1000 
C)  1,000,000 
D)  There is no largest possible value. 
A)  100 
B)  1000 
C)  1,000,000 
D)  There is no largest possible value.

Question 8

What is the mode of the following sample data set?

Accepted Answer

A)  15.1 
B)  9 
C)  5 
D)  22 
A)  15.1 
B)  9 
C)  5 
D)  22

Question 9

A conservationist measures the diameters, in centimeters, of 200 white pine trees in the Allegheny National Forest in Northwest Pennsylvania.The data are summarized with the following five-number summary: ​
Xmin = 18.23, Q1 = 24.29,   = 30.35, Q3 = 36.41, xmax = 42.47
​
Based on the five-number summary, the overall shape of the tree diameters appears to be:

Accepted Answer

A)  heavily right-skewed. 
B)  symmetric. 
C)  heavily left-skewed. 
D)  Data shape can be discerned only from visual methods. 
A)  heavily right-skewed. 
B)  symmetric. 
C)  heavily left-skewed. 
D)  Data shape can be discerned only from visual methods.

Question 10

The Roller Coaster Database maintains a website (www.rcdb.com) with data on roller coasters around the world.Some of the data recorded include whether the coaster is made of wood or steel and the maximum speed achieved by the coaster, in miles per hour.The box plots display the distributions of speed by type of coaster for 145 roller coasters in the United States as downloaded from the site in November 2003.   Are there more wooden or steel roller coasters displayed in this plot?

Accepted Answer

A)  Wooden 
B)  Steel 
C)  There are an equal number of both types of roller coasters. 
D)  We cannot tell the sample sizes from a box plot. 
A)  Wooden 
B)  Steel 
C)  There are an equal number of both types of roller coasters. 
D)  We cannot tell the sample sizes from a box plot.

Question 11

If   , then:

Accepted Answer

A)  the sample is negatively skewed. 
B)  the population must be negatively skewed. 
C)  the sample is positively skewed. 
D)  the population must be positively skewed. 
A)  the sample is negatively skewed. 
B)  the population must be negatively skewed. 
C)  the sample is positively skewed. 
D)  the population must be positively skewed.

Question 12

The smallest numeric value in a data set subtracted from the largest gives the:

Accepted Answer

A)  standard deviation. 
B)  variance. 
C)  mean squared error. 
D)  range. 
A)  standard deviation. 
B)  variance. 
C)  mean squared error. 
D)  range.

Question 13

The following is an abbreviated list of scores from a recent exam.Which exam score is the 15th percentile?

Accepted Answer

A)  98 
B)  28 
C)  51 
D)  56 
A)  98 
B)  28 
C)  51 
D)  56

Question 14

The sample mean is:

Accepted Answer

A)  the same for all distributions. 
B)  a random variable specific to each distribution (i.e., it varies from sample to sample). 
C)  an unknowable quantity. 
D)  a good indicator of the spread of a data set. 
A)  the same for all distributions. 
B)  a random variable specific to each distribution (i.e., it varies from sample to sample). 
C)  an unknowable quantity. 
D)  a good indicator of the spread of a data set.

Calculate for the following sample data set:

The IQ curve is normal, with a mean of 100 and a standard deviation of 15.If "normal" IQ is defined as a score within 1 standard deviation of the mean, what range of scores is considered "normal"?

If we have a distribution with ith deviation from the mean equal to 0, then we know that:

It is known that the body mass index (BMI) of healthy American females follows a normal distribution, with a mean of 22.5 and a standard deviation pf 3.0.Approximately what percentage of female BMI values fall between 16.5 and 28.5?

σ is the symbol for the:

What is the largest possible value of the sample standard deviation?

What is the mode of the following sample data set?

If , then:

The smallest numeric value in a data set subtracted from the largest gives the:

The following is an abbreviated list of scores from a recent exam.Which exam score is the 15th percentile?

The sample mean is:

Why Study Statistics

An Introduction to Statistics and Statistical Inference

Tables and Graphs for Summarizing Data

Probability

Random Variables and Discrete Probability Distributions

Continuous Probability Distributions

Sampling Distributions

Confidence Intervals Based on a Single Sample

Hypothesis Tests Based on a Single Sample

Confidence Intervals and Hypothesis Tests Based on Two Samples or Treatments

The Analysis of Variance

Correlation and Linear Regression

Categorical Data and Frequency Tables

Nonparametric Statistics

Filters

Exam 4: Numerical Summary Measures

Calculate for the following sample data set: ​ ​

The IQ curve is normal, with a mean of 100 and a standard deviation of 15.If "normal" IQ is defined as a score within 1 standard deviation of the mean, what range of scores is considered "normal"?

If we have a distribution with ith deviation from the mean equal to 0, then we know that:

It is known that the body mass index (BMI) of healthy American females follows a normal distribution, with a mean of 22.5 and a standard deviation pf 3.0.Approximately what percentage of female BMI values fall between 16.5 and 28.5?

σ is the symbol for the:

What is the largest possible value of the sample standard deviation?

What is the mode of the following sample data set?

If , then:

The smallest numeric value in a data set subtracted from the largest gives the:

The following is an abbreviated list of scores from a recent exam.Which exam score is the 15th percentile?

The sample mean is:

Why Study Statistics

An Introduction to Statistics and Statistical Inference

Tables and Graphs for Summarizing Data

Probability

Random Variables and Discrete Probability Distributions

Continuous Probability Distributions

Sampling Distributions

Confidence Intervals Based on a Single Sample

Hypothesis Tests Based on a Single Sample

Confidence Intervals and Hypothesis Tests Based on Two Samples or Treatments

The Analysis of Variance

Correlation and Linear Regression

Categorical Data and Frequency Tables

Nonparametric Statistics

Filters

Calculate for the following sample data set: