Statistics Chapter: Descriptive and Inferential

Types of Statistics

• Inferential Statistics: uses sample data to make inferences about the population
• Descriptive Statistics: organizes and summarizes data using numbers and graphs, describes characteristics of the sample

Inferential Statistics

• Objective is to draw conclusions about the population data
• Involves drawing conclusions, performing estimations, and making predictions
• Tools used: Hypothesis test, ANOVA
• Form of results: probability score

Descriptive Statistics

• Objective is to describe the characteristics of the sample data
• Involves collection, organizing, summarizing, and presenting data
• Tools used: Measure of Central Tendency, Measure of Variability
• Results presented in charts, graphs, and tables

Measure of Central Tendency

• Mean
• Mode
• Median

Measure of Variability

• Range
• Variance
• Dispersion

Kinds of Statistics

• Theoretical Statistics
• Mathematical Statistics
• Applied Statistics
• Inferential Statistics
• Descriptive Statistics

Data

• Definition: Individual pieces of factual information recorded and used for the purpose of analysis
• Can be primary or secondary
• Primary data sources: surveys, interviews, pools
• Secondary data sources: annual reports, internet data, open governmental data

Biostatistics

• Definition: application of statistical principles to biological and health fields

Variables

• Definition: any characteristic, number, or quantity that can be measured or counted
• Example variables: Gender, Hair color, Ethnicity, Economic status
• Types of data: Nominal, Ordinal, Qualitative, Quantitative, Discrete, Continuous
• Examples of discrete data: number of students in a class, number of home runs in a baseball game
• Examples of continuous data: height of children, square footage of a two-bedroom house, speed of cars