Module 1

Question 1

Before gathering and analyzing data, we should always ______ the question we wish to answer.

Answer 1

identify

Question 2

Graphs are very useful for examining a data set, as they often reveal ______ and ______ and help us detect outliers.

Answer 2

patterns; trends

Question 3

One useful graph is a _______, also called a bar chart.

Answer 3

histogram

Question 4

A histogram’s _____ represents _____ corresponding to ranges of data;

Answer 4

x-axis; bins

Question 5

A histogram’s _______ indicates the _______of

observations falling into each bin.

Answer 5

y-axis; frequency

Question 6

An ______ is a value that falls far from the rest of the data.

Answer 6

outlier

Question 7

Graphing ___________ on a scatter plot can reveal relationships between ___________.

Answer 7

two variables; two variables (two data sets)

Question 8

Although there may be a relationship between two variables, we cannot conclude that one variable
______ the other. This point is best summarized in the admonition, “_________ does not imply causation.”

Answer 8

“causes”; correlation

Question 9

Be alert to the possibility of _________, which may be responsible for patterns we see when graphing or examining relationships between two data sets.

Answer 9

hidden variables

Question 10

To summarize a data set numerically, we often use __________, also known as summary statistics.

Answer 10

descriptive statistics

Question 11

Three values describe the center, or central tendency, of the data set:

Answer 11

1. mean
2. median
3. mode

Question 12

The _____ is equal to sum of all data points in the set divided by the number of data points.

Answer 12

mean

Question 13

The ______ is the middle value of the data set.

Answer 13

median - half of the data set’s values lie below the median, and half lie above the median.

Question 14

The _____ is the value that occurs most frequently in the data set.

Answer 14

mode - A data set may have multiple modes.

Question 15

The ______, _______, and ________ measure the spread of the data.

Answer 15

range; variance; standard deviation

Question 16

The standard deviation is equal to the _______of the variance.

Answer 16

square root

Question 17

To compare variation in different data sets, we calculate the ___________.

Answer 17

coefficient of variation

Question 18

The coefficient ofvariation measures the size of the ________ relative to the size of the ______.

Answer 18

standard deviation; mean

coefficient of variation = standard deviation/mean

Question 19

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

Answer 19

conditional mean

Question 20

60% of the observations are _____ or ______ to the

60th percentile.

Answer 20

less than; equal

Question 21

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

Answer 21

50th

Question 22

We can quantify the strength of a linear relationship between two variables by calculating the _______.

Answer 22

correlation coefficient

Question 23

The value of the correlation coefficient ranges between __ and ___.

Answer 23

-1; +1

Question 24

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

Answer 24

zero

Question 25

A correlation coefficient near zero does not mean there is no relationship between the two variables; it indicates only that any relationship that does exist is _____.

Answer 25

not linear

Question 26

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

Answer 26

time series

Question 27

_________ provide a snapshot of data across multiple groups at a given point in time.

Answer 27

Cross-sectional data

Question 28

What excel function finds the average?

Answer 28

=AVERAGE(number 1,[number 2], …)

Question 29

What excel function finds the median?

Answer 29

=MEDIAN(number 1, [number 2], …)

Question 30

What excel function finds the mode?

Answer 30

=MODE.SNGL(number 1, [number 2], …)

Question 31

What excel function returns the conditional mean, or average of the cells in a specified range that meet the given criteria?

Answer 31

=AVERAGEIF(range, criteria, [average_range]) * Range contains the one or more cells to which we wish to apply the criteria or condition. * Criteria is the condition that is to be applied to the range. * [average_range] is the range of cells containing the data we wish to average.

Question 32

What excel function returns the k-th percentile of value in the specified array? For example, if we want to know the 95th percentile for an array of data, k would be ____.

Answer 32

=PERCENTILE.INC(array, k); 0.95

Question 33

What excel function finds the variance?

Answer 33

=VAR.S(number 1, [number 2], …)

Question 34

What excel function finds the standard deviation?

Answer 34

=STDEV.S(number 1, [number 2], …)

Question 35

What excel function finds the square root?

Answer 35

=SQRT(number)

Question 36

What excel function finds the number of data points?

Answer 36

=COUNT(value 1, [value 2], …)

Question 37

What excel function finds the minimum number?

Answer 37

=MIN(number 1, [number 2], …)

Question 38

What excel function finds the maximum number?

Answer 38

=MAX(number 1, [number 2], …)

Question 39

What excel function finds the sum of all numbers?

Answer 39

=SUM(number 1, [number 2], …)

Question 40

What does the S stand for in VAR.S and STDEV.S?

Answer 40

S=Sample

Question 41

What excel function finds the correlation coefficient?

Answer 41

=CORREL(array 1, array 2)