Question 1

The mean is the sum of all data values divided by the number of observations.

Accepted Answer

A) True 
 B)False  True

Question 2

In a distribution where there is a long tail towards the right side of the mode, which of the following is true?

Accepted Answer

A)   The distribution is considered normal because it is unimodal
B)   The median is most heavily influenced out of the three central tendencies by the extreme values in the long tail
C)   The mean is the least influenced by the extreme values in the long tail
D)   None of the above are true D

Question 3

The median of the data set is defined as…

Accepted Answer

A)   The exact midpoint of a rank ordered dataset
B)   the arithmetic average.
C)   the largest data point subtract the smallest data point.
D)   the most frequently observed response. A

Question 4

Which of the following measure(s) are commonly used as "typical" measures of center?

Accepted Answer

A)   The Mean, Median, and Mode
B)   The Mean and Median
C)   The Mean and Mode
D)   The Mode and Median

Question 5

A researcher has an experiment with three conditions that generates data on the number of calories worth of food a participant puts on their plate. Which of the following can she do with this data?

Accepted Answer

A)   She can only use the mode for this type of data.
B)   She can calculate means only
C)   She can calculate means and modes. Medians are not informative.
D)   She can calculate means, medians, and mode for each condition

Question 6

In this dataset, one score is missing. However, it is known that the average of the dataset is 60.31. The data values are: 28, 86, 46, 80, 68, 58, 40, 99, 90, 24, 34, 98, X. Find the missing value, X.

Accepted Answer

A)   33
B)   34
C)   32
D)   Insufficient information

Question 7

Adolphe Quetelet made which of the following observations about data that permeates the social sciences, even today?

Accepted Answer

A)   many traits can be measured in a way to make the mean meaningful
B)   the mean is a very important number for a dataset because it is influenced by every datapoint
C)   many traits and characteristics that we measure tend to fall on a normal distribution
D)   Many traits and characteristics that we measure tend to have a fairly uniform distribution.

Question 8

Below are income data for individuals who participated in a recent study.
This data set contains information about the number of hours safe students studied before taking a recent exam. Using this information, answer questions.
 $$\begin{array} { c c } 
\hline \text { Income } & f \
\hline 100000 - 109999 & 9 \
90000 - 99999 & 12 \
80000 - 89999 & 33 \
70000 - 79999 & 21 \
60000 - 69999 & 56 \
50000 - 59999 & 24 \
40000 - 49999 & 19 \
30000 - 39999 & 42 \
20000 - 29999 & 17 \
10000 - 19999 & 6 \
\hline
\end{array}$$ What is the mean?

Accepted Answer

The answer of Below are income data for individuals who...

Question 9

If one data point changes in a dataset, the mean is most likely to change

Accepted Answer

A) True 
 B)False

Question 10

A researcher who is examining stress-related hormones has data on indivdiuals' body mass index. Below are the data
 $$\begin{array} { c c } 
\hline \text { BMI } & f \
\hline 18 & 4 \
19 & 11 \
20 & 6 \
21 & 24 \
22 & 39 \
23 & 33 \
24 & 35 \
25 & 39 \
26 & 41 \
27 & 36 \
28 & 22 \
29 & 16 \
30 & 19 \
\hline
\end{array}$$ What is the median body mass index in this sample?

Accepted Answer

The answer of A researcher who is examining stress-related hormones...

Question 11

How many minutes of television do children watch at home? A researcher surveyed parents and asked them to report the number of minutes per day children spend watching tv. The data are below
 $\begin{array}{llcc}
 \hline \text {Minutes on  } &  \
 \text { TV } &\
\hline 55 \
80 \
75 \
90 \
120 \
40 \
30 \
20 \
60 \
40 \
50 \
120 \
80 \
50 \
60 \
40 \
40 \
50 \
70 \
40 \
\hline
\end{array}$
 What is the mean?

Accepted Answer

The answer of How many minutes of television do children...

Question 12

Which of the following correctly describes finding the center of a grouped frequency distribution?

Accepted Answer

A)   You need to find the midpoint of each grouped interval
B)   The mode is the midpoint of an interval that occurs more frequently
C)   The numbers may differ slightly from using the same data from an ungrouped frequency table.
D)   All of the above are correct.

Question 13

If the mean is less than the median, and the median is less than the mode, the distribution is likely skewed negative

Accepted Answer

A) True 
 B)False

Question 14

The mode is the most commonly observed datapoint in a dataset

Accepted Answer

A) True 
 B)False

Question 15

The following data represent the number of children people have.
$\begin{array}{cc}
\hline  \text {  Number of } &  \
 \text {Kids  } &\
\hline 2 \
1 \
4 \
3 \
3 \
2 \
4 \
1 \
1 \
1 \
2 \
3 \
1 \
4 \
2 \
3 \
2 \
1 \
5 \
1 \
2 \
3 \
1 \
1 \
\hline
\end{array}$
 What is the median?

Accepted Answer

A)   2.1
B)   2.2
C)   2
D)   3

Question 16

Of the three forms of central tendency, the median is most sensitive to outliers.

Accepted Answer

A) True 
 B)False

Question 17

A trimmed mean is most useful when the data is a normal distribution

Accepted Answer

A) True 
 B)False

Question 18

When the data is skewed positive, the mean is expected to be larger than the median and the mode

Accepted Answer

A) True 
 B)False

Question 19

A researcher is running an experiment with two conditions. One in which she asks participants to bite into an apple when remembering a list of words to prevent them from rehearsing the words (i.e., saying them aid memory) and another group where they do not bite into an apple. Below are the data showing the number of words participants were able to recall out of 30.
 $$\begin{array} { c c c c } 
\hline \text { Bite } & f & \text { NoBite } & f \
\hline 5 & 11 & 5 & 4 \
6 & 8 & 6 & 5 \
7 & 14 & 7 & 6 \
8 & 12 & 8 & 14 \
9 & 15 & 9 & 13 \
10 & 16 & 10 & 12 \
11 & 5 & 11 & 15 \
12 & 6 & 12 & 8 \
13 & 3 & 13 & 4 \
14 & 2 & 14 & 9 \
15 & 1 & 15 & 2 \
16 & 0 & 16 & 0 \
17 & 0 & 17 & 1 \
\hline
\end{array}$$ What was the mean of each group?

Accepted Answer

The answer of A researcher is running an experiment with...

Question 20

A research scientist lost a data point out of 100 observations, but luckily has the median. Of the dataset. He asks one of his research assistants to find the missing data point with the remainder 99 observations and the median. Which of the following is true?

Accepted Answer

A)   this task is impossible, because the median does not take into account the magnitude of each observation.
B)   this task is possible, but the research assistant also needs the mode.
C)   This task is possible, but only after the research assistant puts the data into rank order.
D)   This task is possible, but only after the research assistant is given the type of distribution that best represents the data.

Exam 4: Measures of Central Tendency: Whats so Average About the Mean

The mean is the sum of all data values divided by the number of observations.

In a distribution where there is a long tail towards the right side of the mode, which of the following is true?

The median of the data set is defined as…

Which of the following measure(s) are commonly used as "typical" measures of center?

A researcher has an experiment with three conditions that generates data on the number of calories worth of food a participant puts on their plate. Which of the following can she do with this data?

In this dataset, one score is missing. However, it is known that the average of the dataset is 60.31. The data values are: 28, 86, 46, 80, 68, 58, 40, 99, 90, 24, 34, 98, X. Find the missing value, X.

Adolphe Quetelet made which of the following observations about data that permeates the social sciences, even today?

If one data point changes in a dataset, the mean is most likely to change

Which of the following correctly describes finding the center of a grouped frequency distribution?

If the mean is less than the median, and the median is less than the mode, the distribution is likely skewed negative

The mode is the most commonly observed datapoint in a dataset

The following data represent the number of children people have. $\begin{array}{cc}\hline \text { Number of } & \\ \text {Kids } &\\\hline 2 \\1 \\4 \\3 \\3 \\2 \\4 \\1 \\1 \\1 \\2 \\3 \\1 \\4 \\2 \\3 \\2 \\1 \\5 \\1 \\2 \\3 \\1 \\1 \\\hline\end{array}$ What is the median?

Of the three forms of central tendency, the median is most sensitive to outliers.

A trimmed mean is most useful when the data is a normal distribution

When the data is skewed positive, the mean is expected to be larger than the median and the mode

A research scientist lost a data point out of 100 observations, but luckily has the median. Of the dataset. He asks one of his research assistants to find the missing data point with the remainder 99 observations and the median. Which of the following is true?