PSYO 2130 Lecture Notes - Lecture 21: Dbase, Smallest-Circle Problem, Kijiji
8 Dec 2015
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Document Summary
General strategies for approaching a decision that usually help us But that can sometime lead to errors: representative heuristic: used to evaluate similarity between a sample and a population. Ex: imagine tossing a coin six times, what would you expect, 5 heads and 1 tail, or 3 heads or 3 tails. These are independent events, statistically, these two sequences are equally likely to occur. Law of large numbers: a large sample is more similar to the population that a small sample. Knowing that coin tosses are 50/50 is fine on average, overall coin tosses, but which samples are most likely to reflect the population are the large sample. There"s more opportunities for these to play out. In a small sample, it doesn"t necessarily reflect the population. When we use this heuristic we fail to take into account the sample size, so we make a small sample fallacy. Baye"s theorem: judgments should be based on base rates and likelihood ratios.
