1.1: Overview of Stats & Types of Data

Definition of Statistics

data

consists of info coming from observation, counts, measurements, responses

Definition of Statistics

statistics

the science of collecting, organizing, analyzing, and interpreting data to make decisions

2 Types of Data Sets

population

the collection of ALL individuals, outcomes, responses, meausrements, or counts that are of interest

2 Types of Data Sets

sample

• a SUBSET or part of a population

• set of individuals selected from a population (must be representative of population)

2 Types of Data Sets

parameter

numerical description of POPULATION statistic

2 Types of Data Sets

statistics

numerical description of SAMPLE characteristics

2 Branches of Stats

descriptive stats

involves the organization, summarization, display of data

2 Branches of Stats

inferential stats

involves using a sample to draw conclusions about a population

• one basic tool: probability

Types of Data

qualitative data (variables)

consist of attributes, labels, nonnumerical entries (or numbers but not for counting; Ex: U-number)

Types of Data

quantitative data (variables)

• consist of numbers that are measurements or counts

• 2 classifications: discrete & continous

Types of Data

discrete variables

• type of quantitative data

• characterized by gaps or interruptions in values we assume

• all values are whole numbers; NO DECIMAL

  • Ex: number of students at USF

Types of Data

continuous variables

• type of quantitative data

• no gaps or interruptions in values

• DECIMALS ALLOWED

  • Ex: volume of fridges