Sampling Sampling – the process of obtaining a sample from a population Simple Random Sampling – sample selected at random from a population in which every member of the population has an equal chance of being selected Systematic Random Sampling – selecting every n th case from a population Stratified Random Sampling – randomly selecting participants for a sample from predetermined strata (categories) in a population Cluster Sampling – selecting a sample based on pre-organized groups Convenience Sampling – selecting a sample from whatever subjects are available

Variables Independent Variable (IV) – the causal variable – Is typically manipulated by the researcher Dependent Variable (DV) – the effect – Is typically expected to be impacted by the IV Extraneous Variable (XV) or Confounding Variable (CV) – unintended variable that impacts the DV

Hypothesis Research (Alternative) Hypothesis (H 1 or H A ) – what is expected to be found – Directional – the IV is expected to ONLY increase or ONLY decrease the DV – Nondirectional – effect of IV could increase or decrease the DV Null Hypothesis – no effect of IV on DV