Descriptive Statistics: Master Data Analysis for Business Success

Question 1

Which measure of central tendency is most affected by extreme values in a dataset?

Accepted Answer

Mean

Answer

Median

Answer

Mode

Question 2

Which measure of central tendency is less affected by outliers, giving more importance to the middle values of a data set?

Accepted Answer

Median

Answer

Mode

Answer

Range

Question 3

When examining a scatterplot, what valuable information can you glean from it?

Accepted Answer

The nature of the relationship between two variables (positive, negative, or none).

Answer

Only the average value (mean) of one variable.

Answer

The precise frequency of each data point.

Answer

The standard deviation of the variables plotted.

Question 4

What's the main reason for creating a histogram?

Accepted Answer

To show how a quantitative variable is distributed.

Answer

To compare multiple data sets.

Answer

To find the mean and median of a data set.

Answer

To spot outliers in a data set.

Question 5

Which measure of central tendency is most susceptible to the presence of extreme values (outliers)?

Accepted Answer

Mean

Answer

Median

Answer

Mode

Question 6

Which graphical representation is most suitable for displaying the frequency distribution of data values?

Accepted Answer

Histogram

Answer

Scatterplot

Answer

Pie chart

Question 7

Which of the following is NOT a defining characteristic of a normal distribution?

Accepted Answer

Mean, median, and mode are always equal

Answer

Symmetrical bell shape

Answer

Tails extend indefinitely

Question 8

A dataset has a standard deviation of 0. What does this indicate about the data?

Accepted Answer

All data points are identical.

Answer

Data points are spread out widely.

Answer

Cannot be determined from the given information.

Question 9

Which graphical representation is most effective for displaying changes over time?

Accepted Answer

Line graph

Answer

Histogram

Answer

Scatterplot

Question 10

Which measure of central tendency calculates the average of all data points?

Accepted Answer

Mean: The sum of all data points divided by the number of points

Answer

Mode: The most frequently occurring value

Answer

Median: The middle value when the data is arranged in ascending order

Answer

Range: The difference between the smallest and largest data points

Question 11

What is the mathematical formula for calculating the standard deviation?

Accepted Answer

√(Σ(X - μ)² / N)

Answer

(Σ(X - μ)² / N) - 1

Answer

μ - (Σ(X - μ) / N)

Answer

X - (Σ(X - μ)² / N)

Question 12

What does the range of a data set represent?

Accepted Answer

The difference between the minimum and maximum values

Answer

The spread of the data points

Answer

The average value of the data points

Answer

The most common value in the data set

Question 13

Which measure of dispersion is most sensitive to changes caused by extreme values?

Accepted Answer

Range: The difference between the smallest and largest data points

Answer

Standard deviation: The square root of the variance

Answer

Variance: The average squared difference from the mean

Answer

Coefficient of variation: The ratio of the standard deviation to the mean

Question 14

What is the characteristic of a positively skewed distribution?

Accepted Answer

The tail extends to the right

Answer

The tail extends to the left

Answer

The data points are evenly distributed

Answer

The distribution has multiple distinct peaks

Question 15

Which measure of central tendency is most affected by the presence of extreme values?

Accepted Answer

Mean: The sum of all data points divided by the number of points

Answer

Median: The middle value when the data is arranged in ascending order

Answer

Mode: The most frequently occurring value

Answer

Range: The difference between the smallest and largest data points

Question 16

Which measure of dispersion is a dimensionless quantity?

Accepted Answer

Coefficient of variation: The ratio of the standard deviation to the mean

Answer

Range: The difference between the smallest and largest data points

Answer

Standard deviation: The square root of the variance

Answer

Variance: The average squared difference from the mean

Question 17

What does a bimodal distribution indicate?

Accepted Answer

The data has two separate and distinct peaks

Answer

The data is spread evenly over a wide range

Answer

The data is heavily skewed to one side

Answer

The data contains a significant number of outliers

Question 18

When analyzing a data set with outliers, which measure of central tendency is most appropriate?

Accepted Answer

Median

Answer

Mean

Answer

Mode

Question 19

For skewed data, which measure of central tendency is most suitable?

Accepted Answer

Median

Answer

Mean

Answer

Mode

Answer

Range

Question 20

A data set with a mean of 10 and a standard deviation of 2. What is the z-score for a value of 14?

Accepted Answer

2

Answer

-2

Answer

0

Answer

4

Question 21

For comparing multiple data sets with different units of measurement, which graphical representation is most appropriate?

Accepted Answer

Bar graph

Answer

Line graph

Answer

Pie chart

Answer

Scatterplot

Question 22

Which characteristic is NOT part of a well-designed frequency distribution?

Accepted Answer

Random selection of data points

Answer

Equal intervals

Answer

No overlapping intervals

Answer

Appropriate number of intervals

Question 23

A histogram is primarily used to display:

Accepted Answer

Distribution of a single variable

Answer

Relationship between two variables

Answer

Probability of different outcomes

Answer

Trend over time

Question 24

Which of the following is NOT a measure of central tendency?

Accepted Answer

Standard deviation

Answer

Mean

Answer

Median

Answer

Mode

Question 25

Which graphical representation is most suitable for visualizing the distribution of two or more datasets for comparison?

Accepted Answer

Box plot

Answer

Line graph

Answer

Bar chart

Answer

Histogram

Question 26

According to the Empirical Rule, approximately what percentage of data values in a normally distributed dataset fall within one standard deviation of the mean?

Accepted Answer

68%

Answer

95%

Answer

50%

Answer

75%

Question 27

Which characteristic is NOT associated with a normal distribution?

Accepted Answer

Symmetrical around the mode

Answer

Area under the curve sums to 1

Answer

Mean equals Median equals Mode

Answer

Bell-shaped

Question 28

Which statistic measures the dispersion or variability of a dataset?

Accepted Answer

Standard deviation

Answer

Mode

Answer

Median

Answer

Mean

Question 29

A distribution is described as being skewed to the right. What does this indicate?

Accepted Answer

There is a greater concentration of values on the right side of the distribution

Answer

There is a greater concentration of values on the left side of the distribution

Answer

The distribution is symmetrical

Question 30

Which measure of central tendency is most commonly used?

Accepted Answer

Mean

Answer

Mode

Answer

Median

Answer

Range

Question 31

A dataset consists of the following values: 5, 7, 9, 11, 13. what is its median?

Accepted Answer

9

Answer

11

Answer

13

Answer

7

Question 32

Which of these is NOT a measure of central tendency?

Accepted Answer

Range

Answer

Mean

Answer

Median

Question 33

Which measure of central tendency is the least affected by outliers and is therefore preferred for skewed data distributions?

Accepted Answer

Median

Answer

Range

Answer

Mode

Answer

Mean

Question 34

A dataset has a mean of 50 and a standard deviation of 10. Calculate the z-score for a data point with a value of 70.

Accepted Answer

2

Answer

1

Answer

3

Answer

4

Question 35

Which graphical representation is ideal for displaying data distributions and showing the shape, spread, and central tendencies of a dataset?

Accepted Answer

Histogram

Answer

Scatter plot

Answer

Line graph

Question 36

In the context of quartiles, which two quartiles are used to calculate the interquartile range (IQR)?

Accepted Answer

Third quartile and first quartile

Answer

Mean and mode

Answer

Median and range

Question 37

Among the following statistical elements, which one does NOT provide information about the variability or spread of a dataset?

Accepted Answer

Skewness

Answer

Range

Answer

Variance

Answer

Standard deviation

Question 38

Given a population with a standard deviation of 12, what is the approximate probability of randomly selecting a value that is more than 3 standard deviations above the mean?

Accepted Answer

0.0014

Answer

0.05

Answer

0.01

Answer

0.1

Question 39

Which dataset exhibits the largest variance, indicating the most significant spread of data values?

Accepted Answer

{5, 10, 15, 20, 25}

Answer

{0, 2, 4, 6, 8}

Answer

{3, 6, 9, 12, 15}

Answer

{1, 2, 3, 4, 5}

Question 40

One of the limitations of descriptive statistics is that it:

Accepted Answer

Cannot predict future events or make inferences beyond the given dataset

Answer

Can identify patterns and trends

Answer

Can be used to analyze large datasets

Answer

Provides concise summaries of data

Question 41

In a histogram, the height of each bar graphically represents:

Accepted Answer

Frequency or relative frequency of occurrence

Answer

Standard deviation of the data

Answer

Mean of the data

Answer

Range of the data

Question 42

Which measure of central tendency is calculated by adding all the data points and dividing by the total number of data points?

Accepted Answer

Mean

Answer

Range

Answer

Mode

Answer

Median

Question 43

Which statistical measure is best suited for comparing the variability of two datasets that are measured in different units?

Accepted Answer

Coefficient of variation

Answer

Standard deviation

Answer

Range

Question 44

Which of the following is not a measure of skewness?

Accepted Answer

Interquartile range

Answer

Pearson's skewness coefficient

Answer

Moment skewness coefficient

Answer

Bowley's skewness coefficient

Question 45

Which statistical test is most appropriate for comparing the mean values of two independent groups?

Accepted Answer

Independent samples t-test

Answer

Chi-square test

Answer

Analysis of variance

Answer

One-sample t-test

Question 46

Which sampling method ensures that each member of the population has an equal chance of being selected?

Accepted Answer

Simple random sampling

Answer

Systematic sampling

Answer

Stratified sampling

Answer

Quota sampling

Question 47

A dataset has a mean of 50 and a standard deviation of 10. According to the empirical rule, approximately what percentage of the data is expected to be within one standard deviation of the mean?

Accepted Answer

68%

Answer

50%

Answer

34%

Question 48

A researcher is studying the weights of newborn babies. Which of the following measures of central tendency would be most appropriate to use to represent the typical weight of the babies?

Accepted Answer

Median

Answer

Mode

Answer

Range

Answer

Mean

Question 49

A box-and-whisker plot is also known as a:

Accepted Answer

Box plot

Answer

Scatter plot

Answer

Bar chart

Answer

Histogram

Question 50

Which of the following is NOT a measure of skewness?

Accepted Answer

Coefficient of variation

Answer

Pearson's coefficient of skewness

Answer

Bowley's coefficient of skewness

Answer

Fisher-Pearson coefficient of skewness

Question 51

A dataset has a standard deviation of 0. What does this indicate?

Accepted Answer

All data points have the same value.

Answer

The data is normally distributed.

Answer

The data is highly skewed.

Answer

The mean is unreliable.

Question 52

Which of the following is a characteristic of a normal distribution?

Accepted Answer

It is bell-shaped and symmetrical.

Answer

It has a mode that is greater than the mean.

Answer

It is skewed to the right.

Answer

It is only applicable to large datasets.

Question 53

A dataset has a mean of 100 and a standard deviation of 10. Using the empirical rule, what is the probability of randomly selecting a value that is greater than 110?

Accepted Answer

0.1587

Answer

0.9545

Answer

0.8413

Answer

0.6827