Constructing a discrete prior
Suppose American female college students are asked the following question: Do you feel that you are "underweight", "just right", or "overweight"?
Of the students who don't respond "just right", you can denote the proportion of women who believe they're overweight with P
. The value of P
is unknown, but you can construct a probability distribution which reflects your beliefs about its value!
The following table displays prior distributions for three people: Sean, Madison, and Kevin. Each person believes values for P
of 0.5, 0.6, 0.7, 0.8, and 0.9 are plausible, but they assign different probabilities to each:
P Sean_Prior Madison_Prior Kevin_Prior
1 0.5 0.2 0.3 0.1
2 0.6 0.2 0.3 0.1
3 0.7 0.2 0.2 0.2
4 0.8 0.2 0.1 0.3
5 0.9 0.2 0.1 0.3
Which person thinks the proportion of women students believing they are overweight is relatively high?
This exercise is part of the course
Beginning Bayes in R
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