Big Idea 2-Data

Question 1

______ can be stored in variables, lists of items, or standalone constants and can be passed as input to (or output from) procedures.

Answer 1

Data values

Question 2

Computing devices represent data digitally, meaning that the lowest-level components of any value are ________.

Answer 2

bits

Question 3

______ is shorthand for binary digit and is either 0 or 1.

Answer 3

Bit

Question 4

A byte is ____.

Answer 4

8 bits.

Question 5

___________ is the process of reducing complexity by focusing on the main idea. By hiding details irrelevant to the question at hand and bringing together related and useful details, abstraction reduces complexity and allows one to focus on the idea.

Answer 5

Abstraction

Question 6

Bits are grouped to represent abstractions. These abstractions include, but are not limited to, __________, _________, and, ___________.

Answer 6

numbers, characters, and color.

Question 7

True or False?

The same sequence of bits may represent different types of data in different contexts.

Answer 7

True

Question 8

_____ data have values that change smoothly, rather than in discrete intervals, over time.

Answer 8

Analog

Question 9

Some examples of analog data include __________, __________, __________, and __________.

Answer 9

pitch and volume of music, colors of a painting, or position of a sprinter during a race.

Question 10

The use of digital data to approximate real-world analog data is an example of _______.

Answer 10

abstraction

Question 11

Analog data can be closely approximated digitally using a sampling technique, which means measuring values of the analog signal at regular intervals called __________. The _________ are measured to figure out the exact bits required to store each sample.

Answer 11

samples

Question 12

In many programming languages, integers are represented by a fixed number of bits, which limits the range of integer values and mathematical operations on those values. This limitation can result in ______ or other errors.

Answer 12

overflow

Question 13

Comment: Other programming languages provide an abstraction through which the size of representable integers is limited only by the size of the computer’s memory; this is the case for the language defined in the exam reference sheet.

Question 14

In programming languages, the fixed number of bits used to represent real numbers limits the range and mathematical operations on these values; this limitation can result in _______ and other errors. Some real numbers are represented as approximations in computer storage.

Answer 14

round-off

Question 15

Binary (base 2) uses only combinations of the digits _______.

Answer 15

zero and one

Question 16

Decimal (base 10) uses only combinations of the digits _______.

Answer 16

0 – 9

Question 17

Convert 10011011 to decimal.

Answer 17

155

Question 18

_______ can reduce the size (number of bits) of transmitted or stored data.

Answer 18

Data compression

Question 19

True or False: fewer bits mean less information.

Answer 19

False: depends on the data compression type.

Question 20

Comment: The amount of size reduction from compression depends on both the amount of redundancy in the original data representation and the compression algorithm applied.

Question 21

______ data compression algorithms can usually reduce the number of bits stored or transmitted while guaranteeing complete reconstruction of the original data.

Answer 21

Lossless

Question 22

_______data compression algorithms can significantly reduce the number of bits stored or transmitted but only allow reconstruction of an approximation of the original data.

Answer 22

Lossy

Question 23

Lossy data compression algorithms can usually reduce the number of bits stored or transmitted (more than/less than) lossless compression algorithms.

Answer 23

more than

Question 24

In situations where quality or ability to reconstruct the original is maximally important, _______ compression algorithms are typically chosen.

Answer 24

lossless

Question 25

In situations where minimizing data size or transmission time is maximally important, _______ compression algorithms are typically chosen.

Answer 25

lossy

Question 26

_______ is the collection of facts and patterns extracted from data.

Answer 26

Information

Question 27

Comment: Data provides opportunities for identifying trends, making connections, and addressing problems.

Question 28

Digitally processed data may show __________ between variables. A ________ found in data does not necessarily indicate that a causal relationship exists. Additional research is needed to understand the exact nature of the relationship.

Answer 28

correlation

Question 29

_______ is data about data. For example, the piece of data may be an image, while the __________ may include the date of creation or the file size of the image.

Answer 29

Metadata

Question 30

Comment:
Changes and deletions made to metadata do not change the primary data.
Metadata is used for finding, organizing, and managing information.
Metadata can increase the effective use of data or data sets by providing additional information.
Metadata allows data to be structured and organized.

Question 31

Data sets pose challenges regardless of size, such as:

Answer 31

the need to clean data
incomplete data
invalid data
the need to combine data sources

Question 32

__________ is a process that makes the data uniform without changing their meaning (e.g., replacing all equivalent abbreviations, spellings, and capitalizations with the same word).

Answer 32

Cleaning data

Question 33

Problems of bias are often created by the type or source of data being collected.
True/False: Bias is eliminated by collecting more data.

Answer 33

False: Bias is NOT eliminated by simply collecting more data.

Question 34

Large data sets are difficult to process using a single computer and may require _______ systems.

Answer 34

parallel

Question 35

________ of systems is an important consideration when working with data sets, as the computational capacity of a system affects how data sets can be processed and stored.

Answer 35

Scalability

Question 36

________ can be used to process data to acquire information.

Answer 36

Programs

Question 37

Tables, diagrams, text, and other__________ can be used to communicate insight and knowledge gained from data.

Answer 37

visual tools

Question 38

__________ are useful for efficiently finding information.

Answer 38

Search tools

Question 39

Comment: Data filtering systems are important tools for finding information and recognizing patterns in data.

Question 40

Programs such as ________ help efficiently organize and find trends in information.

Answer 40

spreadsheets

Question 41

Some processes that can be used to extract or modify information from data include the following:

• ________ every element of a data set, such as doubling every element in a list, or adding a parent’s email to every student record
• ________ a data set, such as keeping only the positive numbers from a list, or keeping only students who signed up for band from a record of all the students
• ________ or ________ data in some way, such as adding up a list of numbers, or finding the student who has the highest GPA
• ________ a data set through a chart, graph, or other visual representation

Answer 41

• transforming
• filtering
• combining or comparing
• visualizing

Question 42

Comment: Programs are used in an iterative and interactive way when processing information to allow users to gain insight and knowledge about data.

Question 43

Comment: Programmers can use programs to filter and clean digital data, thereby gaining insight and knowledge.

Question 44

________ data sources, ________ data, and _________ data are parts of the process of using programs to gain insight and knowledge from data.

Answer 44

Combining, clustering, classifying

Question 45

__________ can be obtained from translating and transforming digitally represented information.

Answer 45

Insight and knowledge

Question 46

________ can emerge when data is transformed using programs.

Answer 46

Patterns