Chapter 1 Flashcards
Individual
Individuals are the objects described by a set of data. People, animals, things.
Variable
Variables are characteristics of an individual. Can take on different values for different individuals.
Case
A case is an individual about whom or which we have data.
Categorical Variable
A variable that names categories (whether with words or numbers) Ex: hair color, type of car, SSN
Context
The context ideally tells Who was measured, What was measured, How the data were collected, Where the data were collected, and When and Why the study was performed
Data
Systematically recorded information, whether numbers or labels, together with its context
Data Table
An arrangement of data in which each row represents a case and each column represents a variable
Experimental Unit
An individual in a study for which or for whom data values are recorded. Human experimental units are usually called subjects or participants.
Identifier Variable
A categorical variable that records a unique value for each case, used to name or identify it.
Participant
A human experimental unit. Also called a subject.
Population
All the cases in a group being studied, from which samples may be drawn
Quantitative Variable
A variable in which the numbers act as numerical values; always has units.
Record
Information about an individual in a database
Respondent
Someone who answers, or responds, to a survey
Sample
A group specially selected for a research study and which typically represents a picture of the general population.
Subject
A human experimental unit. Also called a participant.
Units
A quantity or amount adopted as a standard of measurement, such as dollars, hours, or grams
Variable
A variable holds information about the same characteristic from many cases
Frequency Table
1
Relative Frequency Table
1
Distribution
1
Pie Chart
Pie charts show the distribution of a categorical variable as a “pie” whose slices are sized by the counts or percents for the categories. A pie chart must include all the categories that make up a whole.
Bar Graph
1
Two-way Table
1
Marginal Distributions
1
Conditional Distributions
1
Side-by-side Bar Graph
1
Association
1
Dotplot
1
Stemplot
1
Histogram
1
SOCS
Describing the Overall Pattern of a Distribution – Remember your SOCS
To describe the overall pattern of a distribution, address all of the following:
Spread – give the lowest and highest value in the data set
Outliers – are there any values that stand out as unusual?
Center – what is the approximate average value of the data (only an estimation)
Shape – does the graph show symmetry, or is it skewed in one direction (see below)
Outlier
An outlier in any graph of data is an individual observation that falls outside the overall pattern of the graph.
Symmetric
1
Sigma
1
x-bar
1
Spread
1
Variability
1
Median
1
Quartiles
1
Q1, Q3
1
IQR
1
Five-number Summary
1
Minimum
1
Maximum
1
Boxplot
1
Resistant
1
Standard Deviation
1
Variance
1
