Ap Computer Science Principles Unit 5: Data

information:

the collection of facts and patterns extracted from data

metadata:

data about data

bar chart:

Count how many times each value in the column appears and make a bar at that height.

histogram

similar to bar chart, but first all numbers in a range or "bucket" are grouped together

*only numerical data

when should you clean data?

-incomplete

-invalid

-combining tabels

what leads to messy data?

-"two" different types of "2"

-different abbreviations

-different spellings

-inconsistent capitalization

what is the goal of cleaning data?

clean data without changing the meaning

two methods of cleaning data...

-look through the data

-use a program to fix

cross tab:

counts how often pairs of values in two columns appear

scatter:

shows combinations of values from two columns

open data:

-open to the public

-shared by government

crowd sourcing:

-social causes (go fund me)

big data:

huge amounts of data

if data is too big...

it can no longer be processed

data bias:

the result of the practice of obtaining input or information from a large number of people via the internet

machine learning:

refers to a computer that can recognize patterns and make decisions without being explicitly programmed