Deck 2: Data Management and Wrangling

Question 1

Which of the following is NOT a process of the data management system?

A) acquire
B) distribute
C) store
D) summarize

Answer 1

summarize

Question 2

Which term represents data items, events, or things stored in a database file?

A) instance
B) entity
C) settings
D) quantitative

Answer 2

entity

Question 3

Mary in the accounting department has been assigned a specific vehicle as her company car to perform audits. This represents which type of relationship?

A) 1 : 1
B) 1 : M
C) M : N
D) M : M

Answer 3

1 : 1

Question 4

Select, From, and Where keywords are statements used in __________.

A) DBMS
B) XML
C) SQL
D) JAVA

Question 5

The primary purpose of a(n) _____________ is to support decision-making and provide a composite view of the organization.

A) data warehouse
B) data mart
C) entity
D) attribute

Question 6

A non-relational database structure that can support the storage of a wide ranges of data, including structured, semi-structured, and unstructured is called ___________.

A) SQL
B) Free Range
C) NoSQL
D) Recreational

Question 7

Mary has been tasked with reviewing a large data file. She wants to begin by first inspecting the number of values in each cell, both numeric and non-numeric, for any blank entries. The plan is to first find the blank or missing values for first review. Using Excel, what function(s) should she use to complete this task?

A) COUNT
B) COUNTA
C) COUNTIF
D) Both COUNT and COUNTA

Question 8

Molly wants to view observations with missing values in Inventory. However, her data set is quite large. What functions should she use to complete her task in R?

A) > is.na (myData.Inventory)
B) > is.na (myData$Inventory)
C) > which (is.na(myData$Inventory))
D) > which (is.na(myData.Inventory))

Question 9

In the presence of outliers in a data set, extremely small or large values, it is preferred to use the __________ instead of the ________ to impute missing variables.

A) median; mean
B) mean; median
C) subset; total
D) average; range

Question 10

In a data set with 18 variables, if 11% of the values, randomly spread across observations, are missing (blank), what is the probable percent of complete and usable observations?

A) 89%
B) 11%
C) 12.27%
D) 7.70%

Question 11

In a data set with 20 variables, if 8% of the values, randomly spread across observations, are missing (blank), what is the probable percent of complete and usable observations?

A) 92%
B) 8%
C) 18.87%
D) 15.29%

Question 12

Using the simple mean imputation strategy, what value would be placed in the missing observation in x₁?

A) 18
B) 82
C) 80
D) 66

Question 13

Using the simple mean imputation strategy, what value would be placed in the missing observation in x₁?

A) 17
B) 84
C) 83
D) 90

Question 14

Using the omission strategy, what value would be placed in the missing observation in x₁?

A) No value because excluded
B) 87
C) 85
D) 69

Question 15

Using the omission strategy, what value would be placed in the missing observation in x₁?

A) No value because excluded
B) 84
C) 83
D) 90

Question 16

When performing an analysis, one technique is called RFM. Which of the following is not reflective of RFM?

A) recency
B) frequency
C) monetary
D) relevancy

Question 17

Mark wants to have a better understanding of his client base at the credit union. To do so, he is running a report to show loan amount approval with corresponding credit scores. He realized the data set is quite large and wants to create categories by grouping. To do this, he needs to do all the following except

A) identify the value he wants to transform into smaller groups or bins.
B) remove 20% of the data to create a training set.
C) ensure the data sets are not overlapping.
D) identify how he wants the observations to be labeled in the bin.

Question 18

In Analytic Solver, Aimee is trying to create a new column called RFM. This column is merging multiple values into one cell. The function to accomplish this is called?

A) TRANSFORM
B) CONCATENATE
C) VARIABLE
D) VLOOKUP

Question 19

The function that provides a natural logarithm in Excel is?

A) The INT function
B) The LN function
C) The YEARFRAC function
D) The VLOOKUP function

Question 20

In R, Mary wants to understand the number of days between rain events in Chicago, IL. What function is used to find the number of rain events between today and January 1, 2019?

A) difftime
B) as.numeric
C) diffdate
D) floor

Question 21

Using R, what is the formula that will allow for the weekday function to display the day of the week for November 15, 2020?

A) >weekdays< (as.Date("2020-11-15")
B) > format(as.Date("2020-11-15"), "%d")
C) > weekdays(as.Date("2020-11-15"))
D) > Sys.Date("2020-11-15")

Question 22

Four observations were binned into one group. In this group, the values are: 40, 45, 66, & 33. What is the average of the group?

A) 48
B) 47
C) 45
D) 46

Question 23

Four observations were binned into one group. In this group, the values are: 40, 45, 38, & 33. What is the average of the group?

A) 41
B) 40
C) 38
D) 39

Question 24

The following table contains 2 variables with 2 observations. A new variable was created named Sum. This is the sum of the values x₁ and x₂ for each observation. What is the average value of Sum if the chart was completed?

A) 120
B) 67
C) 112
D) 128

Question 25

The following table contains 2 variables with 2 observations. A new variable was created named Sum. This is the sum of the values x₁ and x₂ for each observation. What is the average value of Sum if the chart was completed?

A) 106
B) 53
C) 98
D) 114

Question 26

When too many variables are categorized in an analysis, several potential issues may occur. Which of the following is not one of the issues that may occur?

A) model performance suffers.
B) rarely occurring categories may not be captured accurately.
C) difficulty in differentiating among observations.
D) an increase in the number of categories as the data set becomes larger.

Question 27

Henry wants to analyze income, but the sheer number of categories in the data's current form will make a clear analysis less meaningful. In Excel with Analytic Solver, how will Henry determine the frequency of each category to transform his data?

A) Income variable is selected and Analytic solver produces frequency levels for each income category from most to least frequent.
B) Inspect the frequency of Income category: >table(myData$Income).
C) Income variable is selected and Analytic Solver produces a new category for non-use variables.
D) Apply a limit to the number of categories from the drop-down to a reasonable number.

Question 28

Using R, what function is used to evaluate the categories in the variable to identify the dummy variables?

A) referral
B) if
C) ifelse
D) view

Question 29

In the following table, there are four observations with three variables. Which category is the best fit to be transferred into dummy variables?

A) age
B) marital status
C) income
D) none are a good fit for a dummy variable.

Question 30

Ann is analyzing a data set that contains two variables, Job Title and 401K. 401K contains the name of the three companies that carry the retirement accounts. It is mandatory to have an account, thus no observation is blank. If 401K was transformed to dummy variables, how many should be created?

A) 2
B) 3
C) 4
D) 1

Question 31

Transform the marital status into category scores where Single = 1 and Married = 0. How many would have the category score of 0?

A) 1
B) 6
C) 3
D) 0

Question 32

Transform the marital status into category scores where Single = 1 and Married = 0. How many would have the category score of 0?

A) 2
B) 6
C) 4
D) 0

Question 33

Michael is examining a data set and trying to determine which category he can transform into a dummy variable. Of the four variables, Employee Number, Pay Rate, Hire Date, and Sex, which is the best fit to use a dummy variable?

A) employee number
B) pay rate
C) hire date
D) sex

Question 34

Marcus wants to include the month of the year in the analysis as categories. How many dummy variables will be needed?

A) 12
B) 11
C) 6
D) 1

Question 35

Kara is reviewing categories where a series of numbers represent the type of loan. She would prefer the actual name of the loan be retained when running her analysis. Using Analytic Solver, what function will allow Kara to retain the category name instead of recording them in numbers?

A) log function
B) view function
C) IF function
D) head function

Question 36

Using the following table view, Mark wants to create a relationship between the two tables. What will he need to add to establish a relationship?

A) primary key
B) foreign key
C) instances
D) entities

Question 37

The process of retrieving, cleaning, integrating, transforming, and enriching data to support analysis is called data wrangling.

Question 38

A foreign key (FK) is the only unique identifier in a table structure.

Question 39

In R, the following represents how to receive results from column 3, row 2 > myData[3,2].

Question 40

In R, to sort data in descending order, we use a negative parameter in the order function.

Question 41

Simple mean imputation is the best route for replacing large quantities of missing variables within a data set without distorting the relationship among variables.

Question 42

To view only a portion of the data that is of interest, subsetting is used.

Question 43

Converting data from one structure to another is called data transformation.

Question 44

Subsetting is a technique used to convert numerical values into categorical variables.

Question 45

A dummy variable takes on a value of 1 or 0 to describe two categories of a variable.

Question 46

Megan took a phone survey where each question posed had an answer range of unsatisfied to completely satisfied describing her purchase experience. Because the categories are in equal increments, the category can be recoded into a number transforming the category into what is called a category score.