Big Idea 2: Data

Study flashcards for the second unit of the AP Computer Science Principles course.

Data

Collection of facts/statistics

What is the smallest unit of information in the binary system?

Bit

What is a byte?

A unit in the binary system that consists of 8 bits.

Analog data

Continuous and infinite measured data that represents physical quantities, such as sound, light, or temperature.

Digital data

Finite and discrete data that is measured numerically through 0s and 1s (the binary system).

What is the process of converting analog data to digital?

Sampling is the process which is used to convert data from analog to digital by recording the data at regular intervals.

Data abstraction

Using digital data (that leaves out details) to approximate real world analog data.

What is the formula to calculate the maximum amount of values that can be stored in a given number of bits?

2ⁿ - 1 (the n represents the number of bits)

What are the two types of data compression methods?

Lossless and lossy

Characteristics of lossless compression?

No data is lost, inverted pixel colors/brightness, mainly used for text, (png, gif, heic), and compressed packets are decompressed exactly the way they were given.

Characteristics of lossy compression?

Sacrifices data (data is lost) for greater compression, lowers resolution, mainly used for images and sounds, (mp4, mp3, jpeg), and data loss is permanent

Run length encoding is…

A form of lossless data compression that replaces sequences of repeating data values with another value that represents the repeated data.

Big data

Large data sets.

Correlation

The relationship between variables. It DOES NOT imply causation.

Causation

When one event causes another to occur.

Metadata

Data about data that aids with organization.

What challenges do data sets pose?

The need to clean data, incomplete data, invalid data, and the need to combine data sources.

What is data mining?

The process of examining large data sets to identify useful information, trends, and patterns.

Examples of visual data?

Bar charts, scatter plots, line graphs, and histograms.