CRCJ 3001 Lecture 3: LECTURE 3 - Defining & Measuring Variables

• School: Carleton University
• Department: Criminology and Criminal Justice
• Course: CRCJ 3001
• Professor: Donna Mailloux

Document Summary

Lecture 3 defining & measuring variables: hypotheses, operational definitions, measurement validity, measurement reliability, modes of measuring, scales of measurement. A variable is something that varies so that it must have at least 2 levels or values. Scientists examine the causal relationship between variables in an experiment by manipulation, controlling, and measuring variables. Independent variable: the manipulated variable in an experimental model (or grouping variable in quasi-experimental model) Dependent variable: the measured variable (quantitative in this course) Control variable: kept constant across the independent variable so that it does not become a confound variable (one that adversely affects the dependent variable) More than one iv of which there is of the iv w/ a control group levels of the iv both random assignment and pre- existing membership in the iv. A descriptive study (or non-experimental research) only measures variables but does not manipulate them. Shy people are better at reading facial expressions than non-shy people.