WEEK 1

Question 1

Have you ever wondered why some online ads seem to make really accurate suggestions or how some websites remember your preferences?

Answer 1

Cookies can help inform advertisers about your personal interests and habits based on your online surfing, without personally identifying you.

Question 2

Ways to collect and generate data

Answer 2

Forms,
questionnaires and
surveys and
Interviews
Cookies

Question 3

Data collection considerations

Answer 3

Select the right data
how the data will be collected
the data sources
how much data to collect
Solving your business problem
the time frame for data collection.

Question 4

population

Answer 4

Refers to all possible data values in a certain data set.

Question 5

A sample

Answer 5

Is a part of a population that is representative of the population.

Question 6

Data sources

Answer 6

first-party data. This is data collected by an individual or group using their own resources.

second-party data, which is data collected by a group directly from its audience and then sold.

third-party data or data collected from outside sources who did not collect it directly. This data might have come from a number of different sources before you investigated it. It might not be as reliable, but that doesn’t mean it can’t be useful.

Question 7

Data formats

Answer 7

Qualitative data is usually listed as a name, category, or description. In our spreadsheet, the movie titles and cast members are qualitative data.

Quantitative data, which can be measured or counted and then expressed as a number.

Discrete data first. This is data that’s counted and has a limited number of values.

Continuous data can be measured using a timer, and its value can be shown as a decimal with several places.

Nominal data is a type of qualitative data that’s categorized without a set order. In other words, this data doesn’t have a sequence (Yes or No)

Ordinal data, on the other hand, is a type of qualitative data with a set order or scale.

Internal data, which is data that lives within a company’s own systems

External data is, you guessed it, data that lives and is generated outside of an organization.

Structured data is data that’s organized in a certain format, such as rows and columns.

Unstructured data. This is data that is not organized in any easily identifiable manner. Audio and video files are examples of unstructured data because there’s no clear way to identify or organize their content.

Question 8

Unstructured data

Answer 8

Audio files, video files, emails, photos, and social media are all examples of unstructured data.

Question 9

Data Model

Answer 9

is used for organizing data elements and how they relate to one another.
This makes it easy for analysts to enter, query, and analyze the data whenever they need to.
This also helps make data visualization pretty easy because structured data can be applied directly to charts, graphs, heat maps, dashboards and most other visual representations of data.

Question 10

Data elements

Answer 10

Are pieces of information, such as people’s names, account numbers, and addresses.

Question 11

An unfair dataset

Answer 11

Does not accurately represent the population, causing skewed outcomes, low accuracy levels, and unreliable analysis.

Question 12

Data modeling

Answer 12

Is the process of creating diagrams that visually represent how data is organized and structured.

Question 13

Levels of data modeling

Answer 13

Conceptual: business concepts.

Logical: data entities

Physical: physical tasks

Question 14

Conceptual data modeling .

Answer 14

Gives a high-level view of the data structure, such as how data interacts across an organization.
For example, a conceptual data model may be used to define the business requirements for a new database. A conceptual data model doesn’t contain technical details

Question 15

Logical data modeling

Answer 15

Focuses on the technical details of a database such as relationships, attributes, and entities.
For example, a logical data model defines how individual records are uniquely identified in a database. But it doesn’t spell out actual names of database tables. That’s the job of a physical data model.

Question 16

Physical data modeling

Answer 16

Depicts how a database operates. A physical data model defines all entities and attributes used; for example, it includes table names, column names, and data types for the database.

Question 17

Data-modeling techniques

Answer 17

Entity Relationship Diagram (ERD): are a visual way to understand the relationship between entities in the data model.

Unified Modeling Language (UML): Are very detailed diagrams that describe the structure of a system by showing the system’s entities, attributes, operations, and their relationships.

Question 18

Data modeling usefulness

Answer 18

Data modeling can help you explore the high-level details of your data and how it is related across the organization’s information systems.

Data modeling sometimes requires data analysis to understand how the data is put together; that way, you know how to map the data.

And finally, data models make it easier for everyone in your organization to understand and collaborate with you on your data.

Question 19

A data type

Answer 19

A data type tells you what kind of data you’re working with.

Question 20

Data type in a spreadsheet can be one of three things:

Answer 20

a number, a text or string, or a Boolean.

Question 21

Difference between records and fields and rows and columns.

Answer 21

Records and fields can be used for any kind of data table, while rows and columns are usually reserved for spreadsheets.

Question 22

Rows and Columns equals

Answer 22

Records and fields

Question 23

Long data

Answer 23

is data in which each row is one time point per subject, so each subject will have data in multiple rows.

Question 24

Wide data

Answer 24

Lets you easily identify and quickly compare different columns.