Question 1

A stem-and-leaf display is best used to _____

Accepted Answer

A stem-and-leaf display is used to display the shape of the distribution of measurements, allowing for easy visualization of the spread and central tendency of the data.

Question 2

Which percentile describes the third quartile,Q3?

Accepted Answer

The third quartile, Q3, is equivalent to the 75th percentile.

Question 3

If the mean,median,and mode for a given population are all equal,then we know that its distribution is _____.

Accepted Answer

When the mean, median, and mode are all equal, it indicates a symmetrical distribution. This means that there is an equal balance of values on both sides of the center point of the distribution.

Question 4

All of the following can be used to describe quantitative data with the exception of a _____.

Accepted Answer

Pie charts are used to display categorical data, not quantitative data. The other options (histogram, stem-and-leaf display, dot plot, and scatter plot) can all be used to describe or display quantitative data.

Question 5

A ______________ shows the relationship between two quantitative variables.

Accepted Answer

A scatter plot is specifically designed to show the relationship between two quantitative variables. It does so by plotting the two variables as points on a graph, with one variable along each axis. The resulting pattern of points can provide insight into the nature of the relationship between the variables, such as whether it is positive, negative, or nonexistent. None of the other choices are suitable for showing this type of relationship.

Question 6

A ______________ displays the frequency of each group with qualitative data and a __________ displays the frequency of each group with quantitative data.

Accepted Answer

A bar chart is used for qualitative data to show the frequency of each category, while a histogram is used for quantitative data to display the frequency of data within certain ranges or intervals.

Question 7

If a population distribution is positively skewed (i.e.skewed to the right),then,given a random sample from that population,one would expect that the ______________.

Accepted Answer

In a positively skewed (right-skewed) distribution, the mean is typically greater than the median due to the long tail on the right pulling the mean to a higher value. Therefore, the median would be less than the mean.

Question 8

When grouping a large sample of items into classes,the _____ is a better tool than the ____.

Accepted Answer

A histogram is more suitable for grouping a large sample of items into classes because it can efficiently handle and display large datasets, unlike a stem-and-leaf display which becomes cumbersome and less effective with large amounts of data.

Question 9

If one intends to compare the relative variation between two samples involving two different quantitative variables with different measurement scales,then the most appropriate way is to compare the __________ from the two samples.

Accepted Answer

Comparing the coefficients of variation (CV) from the two samples would be the most appropriate way as it is a standardized measure of dispersion that accounts for the different measurement scales of the two variables. The CV is calculated as the ratio of the standard deviation to the mean, expressed as a percentage. By comparing the CVs, we can see which variable has relatively more variation compared to its mean in each sample and can compare the relative variation between the two variables across the two samples.

Question 10

Which of the following graphs is used to summarize qualitative data?

Accepted Answer

A bar chart is the best choice to summarize qualitative data because it displays each category and its frequency, allowing for easy comparison between the categories. Histograms and stem-and-leaf displays are used for numerical data, time series plots are used for data collected over time, and scatter plots are used to show the relationship between two numerical variables.

Question 11

Which of the following is influenced the least by the occurrence of extreme values in a sample?

Accepted Answer

Median is the middle value of a sample, and is not affected by extreme values.

Question 12

_____________ and ____________ are used to describe qualitative (categorical)data.

Accepted Answer

Bar charts and pie charts are commonly used to display qualitative data. Bar charts show the frequency or proportion of each category in a graphical format, while pie charts display the relative size of each category as a slice of a circle. Stem-and-leaf displays, scatter plots, and box-and-whiskers displays are typically used for quantitative data. Histograms are used for both quantitative and categorical data, but are best suited for showing frequency distributions of quantitative variables.

Question 13

Which percentile describes the first quartile,Q1?

Accepted Answer

The first quartile, Q1, represents the 25th percentile of a dataset. Therefore, the correct choice is A, which represents the 25th percentile.

Question 14

All of the following are measures of central tendency except the _____.

Accepted Answer

The range is a measure of variability, not central tendency. Central tendency is measured by the mode, mean, and median, which describe the center of a data set.

Question 15

If a statistics course is determined by three exams.Exam 1 is worth 25% of the course grade.Exam 2 is worth 35% of the course grade.Exam 3 is worth 40% of the course grade.Calculate the term grade for a student with a 52% for the first exam,63% for the second exam,and 75% for the third exam.

Accepted Answer

To calculate the term grade, we need to find the weighted average of the three exam scores.

Exam 1: 52% of 25% = 13%
Exam 2: 63% of 35% = 22.05%
Exam 3: 75% of 40% = 30%

Term grade = 13% + 22.05% + 30% = 65.05%

Therefore, the answer is B) 65.05%.

Question 16

A disadvantage of using grouping (a frequency table)with sample data is that

Accepted Answer

Grouping data can result in the loss of some information and can sometimes lead to less precise descriptive statistics. This is because the grouped data can mask individual variations within each group, leading to less accurate descriptions of the sample data.

Question 17

A plot of the values of a dependent variable y versus the values of an independent variable x is a _____ plot.

Accepted Answer

A scatter plot is used to display the relationship between two continuous variables. It shows the distribution of data points and the pattern of the relationship between the variables. The other options, such as runs, dot, time series, and box plots, are used to display other types of data or relationships between variables.

Question 18

An airline company is,on average,late 10 minutes for arrivals.If the variance for the lateness statistic is 9,then the coefficient of variation is _____.

Accepted Answer

The coefficient of variation is calculated as (standard deviation / mean) * 100. The standard deviation is the square root of the variance, which is 3. Therefore, the coefficient of variation is (3 / 10) * 100 = 30.

Question 19

A measurement that is separated from most of the other measurements is a(n)_____.

Accepted Answer

An outlier is a measurement that is significantly different from the other measurements in a data set. It can be identified as a value that is located far away from the majority of the data points. Therefore, it is the best choice for a measurement that is separated from most of the other measurements.

Question 20

In a given data set,the 25^th percentile is _______________ equal to the lower hinge.

Accepted Answer

The 25th percentile is the same as the first quartile or lower hinge, denoted by Q1. The upper hinge or third quartile, denoted by Q3, is equal to the 75th percentile. Therefore, the 25^th percentile may or may not be equal to Q1 depending on the distribution of the data set. However, it is possible that the 25^th percentile falls exactly on one of the data points in the set, in which case it could be equal to Q1. So, the answer is sometimes.

Quiz 2: Descriptive Statistics

A stem-and-leaf display is best used to _____

Which percentile describes the third quartile,Q3?

If the mean,median,and mode for a given population are all equal,then we know that its distribution is _____.

All of the following can be used to describe quantitative data with the exception of a _____.

A ______________ shows the relationship between two quantitative variables.

A ____ displays the frequency of each group with qualitative data and a displays the frequency of each group with quantitative data.

If a population distribution is positively skewed (i.e.skewed to the right) ,then,given a random sample from that population,one would expect that the ______________.

When grouping a large sample of items into classes,the _ is a better tool than the .

If one intends to compare the relative variation between two samples involving two different quantitative variables with different measurement scales,then the most appropriate way is to compare the __________ from the two samples.

Which of the following graphs is used to summarize qualitative data?

Which of the following is influenced the least by the occurrence of extreme values in a sample?

_ and are used to describe qualitative (categorical) data.

Which percentile describes the first quartile,Q1?

All of the following are measures of central tendency except the _____.

If a statistics course is determined by three exams.Exam 1 is worth 25% of the course grade.Exam 2 is worth 35% of the course grade.Exam 3 is worth 40% of the course grade.Calculate the term grade for a student with a 52% for the first exam,63% for the second exam,and 75% for the third exam.

A disadvantage of using grouping (a frequency table) with sample data is that

A plot of the values of a dependent variable y versus the values of an independent variable x is a _____ plot.

An airline company is,on average,late 10 minutes for arrivals.If the variance for the lateness statistic is 9,then the coefficient of variation is _____.

A measurement that is separated from most of the other measurements is a(n) _____.

In a given data set,the 25^th percentile is _______________ equal to the lower hinge.

Quiz 2: Descriptive Statistics

A stem-and-leaf display is best used to _____

Which percentile describes the third quartile,Q3?

If the mean,median,and mode for a given population are all equal,then we know that its distribution is _____.

All of the following can be used to describe quantitative data with the exception of a _____.

A ______________ shows the relationship between two quantitative variables.

A ______________ displays the frequency of each group with qualitative data and a __________ displays the frequency of each group with quantitative data.

If a population distribution is positively skewed (i.e.skewed to the right) ,then,given a random sample from that population,one would expect that the ______________.

When grouping a large sample of items into classes,the _____ is a better tool than the ____.

If one intends to compare the relative variation between two samples involving two different quantitative variables with different measurement scales,then the most appropriate way is to compare the __________ from the two samples.

Which of the following graphs is used to summarize qualitative data?

Which of the following is influenced the least by the occurrence of extreme values in a sample?

_____________ and ____________ are used to describe qualitative (categorical) data.

Which percentile describes the first quartile,Q1?

All of the following are measures of central tendency except the _____.

If a statistics course is determined by three exams.Exam 1 is worth 25% of the course grade.Exam 2 is worth 35% of the course grade.Exam 3 is worth 40% of the course grade.Calculate the term grade for a student with a 52% for the first exam,63% for the second exam,and 75% for the third exam.

A disadvantage of using grouping (a frequency table) with sample data is that

A plot of the values of a dependent variable y versus the values of an independent variable x is a _____ plot.

An airline company is,on average,late 10 minutes for arrivals.If the variance for the lateness statistic is 9,then the coefficient of variation is _____.

A measurement that is separated from most of the other measurements is a(n) _____.

In a given data set,the 25th percentile is _______________ equal to the lower hinge.

A ____ displays the frequency of each group with qualitative data and a displays the frequency of each group with quantitative data.

When grouping a large sample of items into classes,the _ is a better tool than the .

_ and are used to describe qualitative (categorical) data.

In a given data set,the 25^th percentile is _______________ equal to the lower hinge.