Chapter 2

Question 1

Characteristics of data warehousing

Answer 1

1. Subject oriented
2. Integrated
3. Time-variant (time series)
4. Nonvolatile
5. Web based
6. Relational/multi-dimensional
7. Client/server
8. Real-time
9. Include metadata

Question 2

What is data?

Answer 2

A collection of facts usually obtained as the result of experiences, observations or experiments.
- the lowest level of abstraction

Question 3

Data in Analytics can be categorized into:

Answer 3

• structured data
• unstructured or semi-structured data

Question 4

Structured data can be categorized into:

Answer 4

• categorical
• numerical

Question 5

Categorical data can be cateorized into:

Answer 5

-nominal
- ordinal

Question 6

Numerical data can be categorized into:

Answer 6

• interval
  -ratio

Question 7

Unstructured or semi-structured data can be categorized into:

Answer 7

• textual
• multimedia
• XML/JSON

Question 8

Multimedia data can be cateorized

Answer 8

• image
• audio
• video

Question 9

What are the measures of centrality?

Answer 9

• arithmetic mean
• mean
• mode

Question 10

What are the measures if dispersion?

Answer 10

• range
• variance
• standard deviation
• mean absolute deviation
• quartiles
• box plots
• shape distribution: skewness, kurtosis

Question 11

Define data visualization

Answer 11

use of visual representations to explore, make and communicate data

Question 12

What is the role of dashboards?

Answer 12

they provide visual displays of important information that is consolidated and arranged on a single screen

Question 13

What are the best practices in dashboard design?

Answer 13

1. Benchmark KPIs with industry standards
2. Warp metrics with contextual metadata
3. Validated design by usability specialist
4. Prioritizte and rank alerts and exceptions
5. Pick the right visual constructs
   6- Provide guided analytics

Question 14

What are types of Information Retrieval?

Answer 14

• Document Matching
• Link Analysis
• Search Engines

Question 15

What are types of Web Mining?

Answer 15

• Web content mining
• Web structure mining
• Web usage mining

Question 16

What are types of data mining?

Answer 16

• Classification
• Clusering
• Association

Question 17

What are types of Natural Language Processing?

Answer 17

• POS Tagging
• Lemmatization
• Word Disambiguation

Question 18

What are types of Text Mining?

Answer 18

• Web Mining
• Data Mining
• Information Retrieval
• Natural Language Porcessing

Question 19

Why is text difficult?

Answer 19

• often “unstructured”
• linguistic nature intended for humans, not for computers
• text is relatively “dirty”
• context is important
• goal is to rune text into feature-vector form

Question 20

What is a Document?

Answer 20

one piece of text, no matter how large or small

Question 21

What do individual tokens and term compose?

Answer 21

a document

Question 22

What is a collection of documents called?

Answer 22

a corpus

Question 23

What are representation techniques?

Answer 23

• bag of words
• term frequency
• inverse document frequency
• TFIDF
• N-gramms

Question 24

Bag of words: what does it involve?

Answer 24

creating a “bag” or set of words from a text document

Question 25

Bag of words: what does it only consider?

Answer 25

the presence or absence of words, not their sequence

Question 26

What is term frequency?

Answer 26

measure of how often a term (word) appears in a document

Question 27

What does Invesre document frequency measure?

Answer 27

how important a term is across a collection of documents

Question 28

What is TFIDF?

Answer 28

numerical statistic that combines the TF and IDF scores to reflect the importance of a term in a document within a larger collection

Question 29

What is the role of N-gramms?

Answer 29

they capture local patterns and relationships between adjacent elements in a sequence