Biology 2244A/B Lecture 2: Sampling-strategies

• School: Western University
• Department: Biology
• Course: Biology 2244A/B
• Professor: Jennifer Waugh

Document Summary

Population entire group of individuals about which we want information. Sample part of the population from which we collect information. Inference: gather information about a sample to draw conclusions about the entire population. Sampling design describes how exactly to choose a sample from the population. Non-probability sample sample chosen using personal judgement or human subjectivity. Probability of selecting a specified individual from the population cannot be determined. Convenience sample chooses individuals close at hand. Voluntary response sample lets individuals choose whether to participate or not: people with strong opinions are more likely to respond. Selection bias statistical study"s design systematically favours certain outcomes. Systematic favouritism in data selection process, leading to misleading results. Simple random sampling (srs) all possible samples (groups) of size n from a population is equally likely to be selected / doesn"t favour any part of the population. Best method of achieving a representative sample. Multistage sampling choosing srs within srs.