PO217 Lecture Notes - Lecture 4: Null Hypothesis, Socioeconomic Status, Internal Consistency
Document Summary
Inductive versus deductive model of theory-building: criteria for evaluating theories, correlation or causation, the nature of causal inferences, what is a variable, variables vs. concepts, what is a hypothesis, why are hypotheses so important, null hypothesis. Independent vs dependent variables: spurious, intervening and conditional (reinforcing) variables, levels of measurement, formulating hypothesis, common error in formulating hypothesis, key terms. Inductive model of theory-building: observations empirical generalization hypothesis, deductive model of theory-building, assumptions propositions hypothesis i. e. the ability to predict the lottery numbers before they are drawn. Criteria for evaluating theories: testability, clear directions and instructions for testing. Internal consistency (logical soundness: theories cannot contradict themselves, communicable, explain your theory to others, generality, apply to other settings, simplicity (or parsimony, simple theories are good theories, predictive accuracy, accurately predict future events. What is a variable: any property that varies (i. e. takes on different values) can potentially be a variable, empirically observable properties that take on different values.