Exploratory data analysis

Question 1

anecdotal evidence

Answer 1

Evidence, often personal, that is collected casually rather than by a well-designed study.

Question 2

population

Answer 2

A group we are interested in studying. “Population” often refers to a group of people, but the term is used for other subjects, too.

Question 3

cross-sectional study

Answer 3

A study that collects data about a population at a particular point in time.

Question 4

cycle

Answer 4

In a repeated cross-sectional study, each repetition of the study is called a cycle.

Question 5

longitudinal study

Answer 5

A study that follows a population over time, collecting data from the same group repeatedly.

Question 6

record

Answer 6

In a dataset, a collection of information about a single person or other subject.

Question 7

respondent

Answer 7

A person who responds to a survey.

Question 8

sample

Answer 8

The subset of a population used to collect data.

Question 9

representative

Answer 9

A sample is representative if every member of the population has the same chance of being in the sample.

Question 10

oversampling

Answer 10

The technique of increasing the representation of a sub-population in order to avoid errors due to small sample sizes.

Question 11

raw data

Answer 11

Values collected and recorded with little or no checking, calculation or interpretation.

Question 12

recode

Answer 12

A value that is generated by calculation and other logic applied to raw data.

Question 13

data cleaning

Answer 13

Processes that include validating data, identifying er- rors, translating between data types and representations, etc.