Modules 1-2

Question 1

What should we identify before gathering and analyzing data?

Answer 1

The question we wish to answer

Question 2

What type of graph is useful for examining a data set to reveal patterns and trends?

Answer 2

Histogram

Question 3

In a histogram, what does the x-axis represent?

Answer 3

Bins corresponding to ranges of data

Question 4

In a histogram, what does the y-axis indicate?

Answer 4

The frequency of observations falling into each bin

Question 5

What is an outlier?

Answer 5

A value that falls far from the rest of the data

Question 6

What should we do before deciding on an outlier?

Answer 6

Carefully investigate it

Question 7

What can graphing two variables on a scatter plot reveal?

Answer 7

Relationships between two variables (two data sets)

Question 8

What is a key point regarding correlation and causation?

Answer 8

Correlation does not imply causation

Question 9

What should we be alert to when examining relationships between two data sets?

Answer 9

The possibility of hidden variables

Question 10

What are descriptive statistics also known as?

Answer 10

Summary statistics

Question 11

What three values describe the center of a data set?

Answer 11

• Mean
• Median
• Mode

Question 12

How is the mean calculated?

Answer 12

Sum of all data points divided by the number of data points

Question 13

What is the median?

Answer 13

The middle value of the data set

Question 14

What does the mode represent in a data set?

Answer 14

The value that occurs most frequently

Question 15

Can a data set have multiple modes?

Answer 15

Yes

Question 16

What measures the spread of the data?

Answer 16

• Range
• Variance
• Standard deviation

Question 17

How is the standard deviation calculated?

Answer 17

The square root of the variance

Question 18

What is a conditional mean?

Answer 18

A conditional mean is the mean of a subset of the data that includes all values satisfying a certain condition.

Question 19

What is a percentile?

Answer 19

A percentile is a value below which a certain percentage of observations fall. For example, 60% of the observations are less than or equal to the 60th percentile.

Question 20

What is the median in terms of percentiles?

Answer 20

The median is by definition the 50th percentile of a data set.

Question 21

What is the coefficient of variation?

Answer 21

The coefficient of variation measures the size of the standard deviation relative to the size of the mean.

Question 22

What does the correlation coefficient measure?

Answer 22

The correlation coefficient quantifies the strength of a linear relationship between two variables.

Question 23

What is the range of the correlation coefficient?

Answer 23

The value of the correlation coefficient ranges between -1 and +1.

Question 24

What does a correlation coefficient near zero indicate?

Answer 24

A correlation coefficient near zero indicates a weak or nonexistent linear relationship.

Question 25

What is a time series?

Answer 25

When one of the variables is time, the relationship is known as a time series.

Question 26

What is cross-sectional data?

Answer 26

Cross-sectional data provide a snapshot of data across multiple groups at a given point in time.

Question 27

What should you recall about Excel functions and analyses?

Answer 27

Familiarize yourself with all of the necessary steps, syntax, and arguments for the Excel functions covered in this course.

Question 28

What does the AVERAGEIF function do?

Answer 28

The AVERAGEIF function returns the conditional mean, or average of the cells in a specified range that meet the given criteria.

Question 29

What is criteria in the context of data ranges?

Answer 29

Criteria is the condition that is to be applied to the range.

Question 30

What does [average range] refer to?

Answer 30

[average range] is the range of cells containing the data we wish to average.

Question 31

What does the function PERCENTILE.INC(array, k) do?

Answer 31

Returns the k-th percentile of value in the specified array. ## Footnote For example, if we want to know the 95 percentile for an array of data, k would be 0.95.

Question 32

What is the syntax for calculating variance in a sample?

Answer 32

=VAR.S(number 1, [number 2], ...)

Question 33

What is the syntax for calculating standard deviation in a sample?

Answer 33

=STDEV.S(number 1, [number 2], ...)

Question 34

What does the function SQRT(number) calculate?

Answer 34

Calculates the square root of a number.

Question 35

What is the syntax for counting values?

Answer 35

=COUNT(value 1, [value 2], ...)

Question 36

What does the function MIN(number 1, [number 2], ...) return?

Answer 36

Returns the minimum value from the specified numbers.

Question 37

What does the function MAX(number 1, [number 2], ...) return?

Answer 37

Returns the maximum value from the specified numbers.

Question 38

What is the syntax for summing values?

Answer 38

=SUM(number 1, [number 2], ...)

Question 39

What does the function CORREL(array 1, array 2) calculate?

Answer 39

Calculates the correlation coefficient between two arrays.