QTM 100 Chapter Notes - Chapter 1-5: Simple Random Sample, Dependent And Independent Variables, Confounding
9 Feb 2020
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Associated variables can also be called dependent variables and vice-versa: anecdotal evidence typically is composed of unusual cases that we recall based on their striking characteristics and not reliable, this introduces bias into a sample. For instance, if only 30% of the people randomly sampled for a survey actually respond, then it is unclear whether the results are representative of the entire population. This non- response bias can skew results: another common downfall is a convenience sample, where individuals who are easily accessible are more likely to be included in the sample. For instance, if a political survey is done by stopping people walking in the bronx, this will not represent all of new york city. For instance, researchers may collect information via surveys, review medical or company records, or follow a cohort of many similar individuals to study why certain diseases might develop. In each of these situations, researchers merely observe the data that arise.
