LECTURE 1 Introduction to Statistics SP110 STATISTICS FOR PSYCHOLOGY
OUTLINE What is Statistics? Branches of Statistics Population and Sample Data and Variable Types of Data and Variables Parameter and Statistic Levels of Measurement Independent and Dependent Variables Parametric and Non-Parametric Tests
WHAT IS STATISTICS?
Uses of Statistics • Organize and summarize information • Determine exactly what conclusions are justified based on the results that were obtained Goals of statistical procedures • Accurate and meaningful interpretation • Provide standardized evaluation procedures
BRANCHES OF STATISTICS There are two main branches of statistical methods Descriptive statistics • Psychologists use descriptive statistics to summarize and describe a group of numbers from a research study. Inferential statistics • Psychologists use inferential statistics to draw conclusions and to make inferences that are based on the numbers from a research study but that go beyond the numbers.
POPULATION AND SAMPLE Population • The set of all the individuals of interest in a particular study • Vary in size; often quite large Sample • A set of individuals selected from a population • Usually intended to represent the population in a research study
DATA AND VARIABLE Data • Measurements or observations of a variable Variable • Characteristic that can have different values
TABLE is aVARIABLE?
TABLE is a VARIABLE
SIZE OF A TABLE is aVARIABLE?
SIZE OF A TABLE is a VARIABLE
Types of Data Types of Variables • Quantitative Data • Quantitative Variable • Discrete • Continuous • Qualitative Data • Qualitative Variable TYPES OF DATA AND VARIABLES