Final Exam Material

Question 1

what is data sourcing?

Answer 1

(also known as data collection) is the process of extracting data from external or internal sources

data sources include:
enterprise databases (historical data, customer sign-up information), web data (web pages, social media), mobile data (apps, GPS), government data, and survey data

Question 2

why use surveys as a data sourcing model?

Answer 2

efficient way to collect information about a large group of people, flexible medium that can measure attitudes/knowledge/preferences/etc., standardized–so less susceptible to error, easy to administer, can be tailored exactly by the topic you wish to study

Question 3

keys to effective surveying

Answer 3

begin with clear purpose, know what you want to be able to do with the data ahead of time, identify the most logical group to survey

Question 4

parts of a survey: title

Answer 4

should reflect the content of the survey, be easy to understand, and be concise

Question 5

parts of a survey: introduction statement

Answer 5

provides brief summary of survey’s purpose, includes information about the respondent’s confidentiality, motivates the respondent to complete the survey, provides an estimate of the time required to complete, should be clear and concise

Question 6

parts of a survey: questions

Answer 6

include directions for completing, each question should have a defined objective, notice question wording, lead with high-interest questions, close with demographic questions, and keep it brief by eliminating unnecessary questions

Question 7

parts of a survey: survey logic

Answer 7

respondent should only be asked questions that apply to them, asking respondents to reply to questions that do not apply to them can lead to confusion and unreliable results (skip and display)

Question 8

parts of a survey: closing statement

Answer 8

thank the respondent for participating, provide contact information for questions, explain how the survey results will be disseminated, if any incentive is offered–provide relevant information

Question 9

double barreled questions

Answer 9

questions that attempt to get at multiple issues at once, and so tend to receive incomplete or confusing answers (ex. do you like pizza and ice cream?)

Question 10

high-interest questions

Answer 10

should be at beginning of survey, most important

Question 11

demographic (sensitive) questions

Answer 11

should be at end of survey, not as important but very helpful

Question 12

question types: open-ended

Answer 12

provides respondents the opportunity to express themselves in their own words, no correct answers, often elicit unanticipated responses which provide new directions for research, can be difficult to interpret/analyze if clear themes do not emerge, short answer text or essay format

Question 13

question types: closed-ended

Answer 13

more difficult to write than open-ended questions, have a finite set of answers, responses are easy to standardize and analyze statistically, may miss pertinent information if a key answer is not provided to respondents (can be corrected by using “other” response option)

Question 14

advantages and disadvantages of open-ended questions

Answer 14

advantages:
respondents can define central issues, address the issue of “why”

disadvantages:
can be time consuming, results can be more challenging to analyze, leading questions can lead to less reliable results

Question 15

advantages and disadvantages of closed-ended questions

Answer 15

advantages:
easy to answer, easier to analyze results

disadvantages:
cannot address the issue of “why,” limited options available to respondents, can be hard to gauge results (ex a 2 on a ranking can mean different things to different respondents)

Question 16

types of survey logic (skip vs display)

Answer 16

skip logic: allows you to send respondents to a future point in the survey based on how they answer a question. (ex. if a respondent indicates that they don’t fit to your respondent criteria, they could immediately be skipped to the end of the survey.)

display logic: allows you to display questions conditionally based on the respondent’s answers to previous questions.

Question 17

survey administration: population vs sample

Answer 17

population: the larger set of individuals you wish to understand
sample: a subset selected from a population to survey

Question 18

sampling techniques: simple random sample

Answer 18

members of the subset are chosen completely at random so that every member of the population has an equal probability of being selected

Question 19

sampling techniques: stratified sample

Answer 19

the population is divided up into relatively homogeneous groups; then, a proportionate probability sample is drawn from the groups

Question 20

sampling techniques: convenient sample

Answer 20

members of the subset are selected according to their availability

Question 21

survey analysis: reporting the results

Answer 21

a final report should include: purpose, design of survey, administration process, data analysis, and findings

Question 22

primary data

Answer 22

data collected from the original source by the investigator himself/herself for a specific purpose

Question 23

secondary data

Answer 23

data collected by someone else for some other purpose (but being utilized by the investigator for another purpose) or not from the original source

Question 24

advantages and disadvantages of primary data

Answer 24

advantages:
data collected is specific to the problem, quality of data can be ensured, may be possible to obtain additional data

disadvantages:
expensive, time consuming, requires setup and manpower

Question 25

advantages and disadvantages of secondary data

Answer 25

advantages: cost-effective, quicker to gather disadvantages: you cannot decide what is collected (maybe out of date or inaccurate), no control over quality, hard to obtain additional data

Question 26

robots.txt file

Answer 26

A text file that provides special instructions (e.g. privacy information) about a Web site to Web crawlers. Web site owners use the robots.txt file to give instructions to web robots (e.g., scrapers) about their site The file is structured to specify what parts of the site robots are DISALLOWED to examine

Question 27

API

Answer 27

Application Programming Interface intermediary software that allows two applications to talk to each other, through Web API, a sourcing application can talk to a website (i.e., extract information from the website), most websites require developer accounts to access their Web API

Question 28

transactional information

Answer 28

encompasses all of the information contained within a single business process or unit of work, and its primary purpose is to support the performing of daily operational tasks

Question 29

analytical information

Answer 29

encompasses all organizational information, and its primary purpose is to support performing of managerial analysis tasks

Question 30

examples of transactional information

Answer 30

airline ticket, sales receipt, packing slip

Question 31

examples of analytical information

Answer 31

product statistics, sales projections, future growth, trends

Question 32

data quality

Answer 32

data that are fit for use by data consumers and satisfies the requirements of its intended use (depends on what is needed to know)

Question 33

high-quality data

Answer 33

data that are relevant and accurately represent their corresponding concepts

Question 34

high-quality information

Answer 34

information that is relevant and a faithful representation of what is being reported

Question 35

characteristics and examples of high-quality information

Answer 35

accurate: is there an incorrect value in the information? (name spelled correctly? is the dollar amount recorded properly?) complete: is a value missing from the information? (is the address complete?) consistent: is aggregate or summary information in agreement with detailed information? (do all columns equal the true total of the individual item?) timely: is the information current with respect to business needs? (is information updated weekly, daily, or hourly?) unique: is each transaction and event represented only once in the information? (are there any duplicate customers?)

Question 36

benefits of high-quality information

Answer 36

Information is everywhere in an organization Employees must be able to obtain and analyze the many different levels, formats, and granularities of organizational information to make decisions Successfully collecting, compiling, sorting, and analyzing information can provide tremendous insight into how an organization is performing

Question 37

examples of low information quality

Answer 37

missing information, incomplete information, probable duplicate information, potential wrong information, inaccurate information

Question 38

sources of low-quality information

Answer 38

four primary sources: - customers intentionally enter inaccurate information to protect their privacy - different entry standards and formats - operators enter abbreviated or erroneous information by accident or to save time - third party and external information contains inconsistencies, inaccuracies, and errors - parallel data entry (duplicates)

Question 39

costs/consequences of low-quality information

Answer 39

potential business effects resulting from low quality information include: - inability to accurately track customers - difficulty identifying valuable customers - inability to identify selling opportunities - marketing to nonexistent customers - difficulty tracking revenue - inability to build strong customer relationships

Question 40

why is data cleaning important?

Answer 40

improves your data quality and in doing so, increases overall productivity. When you clean your data, all outdated or incorrect information is gone - leaving you with the highest quality information

Question 41

data cleaning strategies and activities

Answer 41

replace values (missing values in a column--null values, need to change a value everywhere it appears), remove duplicate rows (redundant data/repeated rows--dups), split column by delimiter (multiple values in one cell), trim (extra spaces before or after text), lowercase/uppercase/capitalize each word (text is mis-capitalized), create custom column-"glue" (values spread across multiple columns), create conditional column as a test (invalid data due to incorrect format), extract text using delimiter (text embedded in cell)

Question 42

replacing values

Answer 42

transform tab, replace values

Question 43

removing duplicates

Answer 43

home tab, remove rows, remove duplicates

Question 44

removing blank rows

Answer 44

sort, delete by number of blank rows

Question 45

trim

Answer 45

transform tab, format, trim

Question 46

split column by delimiter (i.e. how to choose delimiter)

Answer 46

home, split column, by delimiter

Question 47

glue/concentrate multiple values

Answer 47

add column tab, custom column, & " " &

Question 48

capitalization

Answer 48

add column, format, whichever option needed

Question 49

conditional column as a test

Answer 49

add column, conditional column, parameters

Question 50

extract text using delimiter

Answer 50

add column, extract, feature needed

Question 51

what is a relational database?

Answer 51

databases that store information in related two-dimensional tables

Question 52

what is the purpose of a database?

Answer 52

- to store data - to provide an organizational structure for data - to provide a mechanism for querying, creating, modifying, and deleting data

Question 53

what can be stored in a database?

Answer 53

specific details about each type of object

Question 54

how is the design of a database communicated?

Answer 54

through data models

Question 55

what is a data model?

Answer 55

graphical, logical structures that detail the relationships among data fields

Question 56

what is included in a data model?

Answer 56

tables, data fields/attributes, keys (primary and foreign), relationships

Question 57

what is a database table (entity)?

Answer 57

a representation of one type of object

Question 58

two views of database table

Answer 58

model (an abstract representation of the structure) or with records in a two-dimensional grid

Question 59

what is a record?

Answer 59

A record is a set of data for the fields in a table

Question 60

what is a data field (attribute)?

Answer 60

the smallest or most basic unit of information that is stored about an object

Question 61

well-structured vs ill-structured data fields

Answer 61

only one type of information should be stored in each field

Question 62

database keys

Answer 62

create a logical relationship between two tables

Question 63

what is a primary key?

Answer 63

a data field that uniquely identifies each row in a table (within each table, the values in the PK column can never repeat or be duplicated)

Question 64

which attribute should be selected as a primary key?

Answer 64

typically a UNIQUE value (like customer_id)

Question 65

what is a foreign key?

Answer 65

a primary key of one table that appears as an attribute in another table and acts to provide a logical relationship between the two tables

Question 66

characteristics of foreign keys

Answer 66

foreign key and crow's foot are always together, primary key featured in other data tables

Question 67

parent table and child table

Answer 67

To determine which table should be the child and which should be the parent, determine which makes more sense based on the business context

Question 68

how to determine parent and child tables

Answer 68

Parent: ONE Child: MANY

Question 69

crow's foot notation

Answer 69

When creating a logical relationship between two tables, one table gives its primary key to the other. The table that gives its primary key is the parent table, and it has a perpendicular line (|) on the outer edge of its end of the line. The other table is the child table and it has a crow's foot on the outer edge of its end of the line.

Question 70

referential integrity

Answer 70

a property of data stating that all its references are valid

Question 71

database vs. lists (spreadsheets)

Answer 71

with lists: multiple objects in the same row create modification problems in lists--update problems, deletion problems, insertion problems

Question 72

advantages of using a database

Answer 72

increased flexibility, increased scalability and performance, reduced information redundancy, increased information integrity (quality), increase information security

Question 73

What is a query?

Answer 73

the identification and transformation of data to answer a question

Question 74

How are queries used in organizations?

Answer 74

to answer business questions and generate reports for decision-making (ex. sales reports by region)

Question 75

How to determine query requirements (e.g. which tables need to be used)

Answer 75

dissect key parameters (important elements of the questions that need to be part of the query)

Question 76

Single table queries

Answer 76

use only one table as their data source, PKs and FKs must be kept in mind (different meanings)

Question 77

Aggregation (sum, min, max, median, average, count values, count distinct values)

Answer 77

sum: returns total of the column min: returns lowest value in the column max: returns highest value in column median: returns median of column's values (middle) average: average of column's values count values: returns the number of values in the column count distinct values: returns the number of different and unique values in a column

Question 78

When to use aggregation?

Answer 78

when one wants an entire column to be summarized into a single value

Question 79

Aggregating within groups (group by)

Answer 79

Using the Group By menu, specify a column that contains the grouping column and what column should be aggregated and how Any type of aggregation that can be performed on an entire column can be performed within groups The query will automatically determine how many groups exist by examining the grouping column's distinct values

Question 80

Sorting (ascending, descending)

Answer 80

arranges the rows in the query by examining the values in a specified column Ascending: A to Z, Lowest Number to Highest Number Descending: Z to A, Highest Number to Lowest Number

Question 81

Filtering (text filter, number filter)

Answer 81

removing values that meet specified criteria Can specify the entire cell contents ("is"), partial cell contents ("contains"), or starting with a specific character ("begins with") Can specify operators: equal to, not equal to, greater than, less than, greater than or equal to, less than or equal to

Question 82

Multiple filtering criteria (AND, OR)

Answer 82

When combining multiple clauses, must specify whether they are connected via AND (more conservative) or OR (less conservative) AND: both test must be true OR: only one test have to be true

Question 83

Multi tables queries

Answer 83

Goal: Moving information into a single table so that single table queries can be applied

Question 84

When to use append

Answer 84

If multiple tables have the exact same columns and store similar information, the tables can be appended to form a single table

Question 85

When to use merge

Answer 85

For queries that require data from multiple different tables, the tables must first be merged together using a join Merge selects all rows from both participating tables or queries as long as there is a match between the specified columns

Question 86

What is data visualization?

Answer 86

The presentation of data in a pictorial or graphical format Human brains process information more easily graphically than analytically (tables) Allows trends or patterns in the data to be identified, more difficult concepts to be easily grasped, the presentation of analyses results

Question 87

Types of variables (numerical)

Answer 87

Variables to which a number is assigned as a quantitative value

Question 88

Types of variables (categorical)

Answer 88

Variables defined by the classes or categories into which an individual member falls

Question 89

Types of variables (numerical, discrete)

Answer 89

Reflects a number obtained by counting—no decimal. Gaps between possible values (e.g. number of orders 1, 5, 7 etc. No 1.5 orders)

Question 90

Types of variables (numerical, continuous)

Answer 90

Reflects a measurement; the number of decimal places depends on the precision of the measuring device. (e.g. money spent 228.58 dollars)

Question 91

Types of variables (categorical, nominal)

Answer 91

Name only (e.g. Gender - female, male, hair color - black, brown, red etc).

Question 92

Types of variables (categorical, ordinal)

Answer 92

Nominal categories with an implied order (e.g. low, medium, high).

Question 93

Determining what type of chart to use

Answer 93

requirements, content you are trying to visualize, attributes available, does the data need to be aggregated or filtered, data needed for the chart

Question 94

Elements of a graph (title, axis titles, legend, data labels)

Answer 94

Title: a descriptive text that uniquely identifies the graph. The title should not just repeat the labels, but add information specific to what the data represents. Axis titles: a short descriptive label that represents each axis. Legend: Many charts will use different visual properties such as colors or shapes to represent different values of data. A legend identifies what these associations mean. Not every chart has a legend. Data labels: Numerical values for each data point visualized in the graph. Data labels are not applicable to every graph (e.g. map, word cloud)

Question 95

Filters

Answer 95

Remove all but the data you want to focus on (visual, page, report filters), additional attributes can also be added as a filter (even though when they are not one of the chart fields)

Question 96

Slicers

Answer 96

An alternate way of filtering that is displayed on the report canvas, can add onto report just like any other visualization, can be used to display commonly-used or important filters on the report canvas for easier access, and make it easier to see the current filtered state without having to open the filter menu

Question 97

What is a dashboard?

Answer 97

Set of visualizations (usually interactive that allow the reader to draw their own conclusion by looking at the data

Question 98

Purpose of dashboards

Answer 98

Help to summarize and monitor events or activities at a glance by providing key insights and analysis about data on one or more pages or screens

Question 99

What is an infographic?

Answer 99

Data visualization tools that present complex data and information in many visualizations on one page Static set of images that lead the reader to a conclusion that is pre-ordained by the author Information + Graphic Simplify, condense, engage, and enhance

Question 100

Design guidelines

Answer 100

Consistent, complimentary colors across visualizations but use contrasting colors within Color text so it is visible (contrast) Use both text and graphics Maximum of 3 fonts Include a title, icons, lines/arrows, "whitespace," alignment, repetition, proximity