descriptive statistical

Question 1

What is descriptive statistics?

Answer 1

Descriptive statistics is a branch of statistics that deals with summarizing and organizing data.

Question 2

True or False: Descriptive statistics can infer conclusions about a population from a sample.

Answer 2

False

Question 3

What are the two main types of descriptive statistics?

Answer 3

Measures of central tendency and measures of variability.

Question 4

Fill in the blank: The three measures of central tendency are mean, median, and _____.

Answer 4

mode

Question 5

What is the mean?

Answer 5

The mean is the average of a set of numbers, calculated by dividing the sum of the values by the number of values.

Question 6

How is the median determined?

Answer 6

The median is the middle value when the data set is ordered from least to greatest.

Question 7

What is the mode?

Answer 7

The mode is the value that appears most frequently in a data set.

Question 8

True or False: A data set can have more than one mode.

Answer 8

True

Question 9

What is a frequency distribution?

Answer 9

A frequency distribution is a summary of how often each value occurs in a data set.

Question 10

What does a histogram represent?

Answer 10

A histogram represents the frequency distribution of numeric data using bars.

Question 11

What is the range of a data set?

Answer 11

The range is the difference between the maximum and minimum values in a data set.

Question 12

What are quartiles?

Answer 12

Quartiles are values that divide a data set into four equal parts.

Question 13

What is the interquartile range (IQR)?

Answer 13

The interquartile range is the difference between the first and third quartiles (Q3 - Q1).

Question 14

True or False: The standard deviation is a measure of how spread out the values in a data set are.

Answer 14

True

Question 15

What is variance?

Answer 15

Variance is the average of the squared differences from the mean.

Question 16

What does a box plot represent?

Answer 16

A box plot represents the distribution of a data set based on five summary statistics: minimum, first quartile, median, third quartile, and maximum.

Question 17

Fill in the blank: In a box plot, the line inside the box represents the _____.

Answer 17

median

Question 18

What is a percentile?

Answer 18

A percentile is a measure indicating the value below which a given percentage of observations in a group of observations falls.

Question 19

What is the purpose of descriptive statistics?

Answer 19

The purpose of descriptive statistics is to summarize and describe the main features of a data set.

Question 20

True or False: Descriptive statistics can be used for inferential purposes.

Answer 20

False

Question 21

What type of data is best suited for a pie chart?

Answer 21

Categorical data.

Question 22

What is a scatter plot used for?

Answer 22

A scatter plot is used to determine the relationship between two quantitative variables.

Question 23

Fill in the blank: The ____ is the sum of all data points divided by the number of points.

Answer 23

mean

Question 24

What does the term ‘skewness’ refer to?

Answer 24

Skewness refers to the asymmetry of the distribution of values in a data set.

Question 25

True or False: A positively skewed distribution has a longer tail on the right side.

Answer 25

True

Question 26

What is kurtosis?

Answer 26

Kurtosis is a measure of the 'tailedness' of the probability distribution of a real-valued random variable.

Question 27

What is a cumulative frequency distribution?

Answer 27

A cumulative frequency distribution shows the cumulative total of frequencies up to a certain point.

Question 28

Fill in the blank: The ____ of a data set is the value that occurs most frequently.

Answer 28

mode

Question 29

What is the difference between population and sample in statistics?

Answer 29

A population includes all members of a specified group, while a sample is a subset of the population.

Question 30

What is a dot plot?

Answer 30

A dot plot is a simple graphical display that uses dots to represent the frequency of values in a data set.

Question 31

True or False: Descriptive statistics can help identify outliers in data.

Answer 31

True

Question 32

What is the purpose of using measures of central tendency?

Answer 32

To summarize a data set with a single representative value.

Question 33

What is a stem-and-leaf plot?

Answer 33

A stem-and-leaf plot displays quantitative data while preserving the original data values.

Question 34

Fill in the blank: The ____ is a measure that provides an idea of the average distance of data points from the mean.

Answer 34

standard deviation

Question 35

What is the relationship between variance and standard deviation?

Answer 35

Standard deviation is the square root of variance.

Question 36

What does a normal distribution look like?

Answer 36

A normal distribution is bell-shaped and symmetric about the mean.

Question 37

True or False: In a normal distribution, approximately 68% of the data falls within one standard deviation of the mean.

Answer 37

True

Question 38

What is a frequency polygon?

Answer 38

A frequency polygon is a graphical representation of the frequency distribution of a dataset using line segments.

Question 39

Fill in the blank: The ____ of a data set is calculated as the square root of the variance.

Answer 39

standard deviation

Question 40

What is a bar graph used for?

Answer 40

A bar graph is used to compare different categories of data.

Question 41

What does a negative skew indicate?

Answer 41

A negative skew indicates that the left tail of the distribution is longer or fatter than the right tail.

Question 42

What is a z-score?

Answer 42

A z-score indicates how many standard deviations a data point is from the mean.

Question 43

Fill in the blank: A ____ is a visual display of the distribution of data points in a data set.

Answer 43

histogram

Question 44

What is a two-way table?

Answer 44

A two-way table is used to summarize data that involves two categorical variables.

Question 45

True or False: The mean is always a better measure of central tendency than the median.

Answer 45

False

Question 46

What is a potential drawback of using the mean?

Answer 46

The mean can be heavily influenced by outliers.

Question 47

What type of data is best suited for a bar graph?

Answer 47

Categorical data.

Question 48

What is a scatter plot used for?

Answer 48

To show the relationship between two quantitative variables.