AP Statistics Variables Vocabulary Statistics The science of
AP Statistics Variables
Vocabulary Statistics – The science of data. n Individuals – The objects described by a set of data. Can be people, animals or things. n Population – Set of all possible individuals. n Variable – Any characteristic of an individual. n
Exploratory Data Analysis (Descriptive Statistics) Basic Strategies: n 1. Examine each variable by itself, then move on to study relationships between variables. n 2. Graph and summarize specific aspects of the data. n
More Vocabulary Univariate Data – Describes a single aspect of Data (age). n Bivariate/Multivariate Data – Describes more than one aspect (gender and age). n
Types of Variables Categorical Variable – Describes a category or group an individual belongs to. *Groups can’t be rank-ordered. n Examples – Gender, eye color, age groupings. n
Types of Variables Quantitative Variables – Uses numerical values to describe the variable. One can rank order and can perform arithmetic operations on quantitative data. n Can be further broken down into Discrete and Continuous quantitative variables. n
Quantitative Variables Discrete - Isolated points on a number line (ages, grades). n These are items which can be counted. n Continuous – Can exist in an interval on a number line (GPA’s, task completion times) n These are item which must be measured. n
Distribution of a Variable n What values a variable takes and how often it takes them.
Qualitative Graphs n Bar Graphs
Qualitative Graphs Continued n Circle Graphs:
Homework n Worksheet - Categorical vs. Quantitative Variables
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