Lecture 20: judgement and decision making

Question 1

deterministic

Answer 1

deductive (syllogism)

Question 2

probabilistic

Answer 2

inductive (observe evidence, draw up conclusion)

Question 3

normative theory of reasoning

Answer 3

how one ought to reason (e.g. rules of logic)

Question 4

descriptive theory of reasoning

Answer 4

how people actually reason(e.g. biases, heuristics)

Question 5

Bleeding gums: gingivitis? (deterministic or probabilistic?)

Answer 5

probabilistic

Question 6

base rate

Answer 6

the overall likelihood of the hypothesis being true

Question 7

____ of all women with breast cancer have a positive mammogram

Answer 7

80%

Question 8

You need to consider the ____ ____ when looking at mammograms

Answer 8

base rate, cause only 10 out of 1000 get breast cancer

Question 9

Baye’s theorem

Answer 9

P(H/E) = P(H/E)P(H)
_________
P(E/H)P(H)+P(hypothesis)+P(evidence)

Question 10

P(E/H)

Answer 10

current evidence; probability of current evidence if hypothesis is true

Question 11

_

P(E/H)

Answer 11

probability of hypothesis independent of current evidence

Question 12

P(H)

Answer 12

base rate; probablility of hypothesis independent of current evidence

Question 13

Experiment 1: no description given, probability of Jack being a lawyer or engineer

Answer 13

people chose correct probability

Question 14

Experiment part 2: engineer description

Answer 14

people ignore the base rate

Question 15

Experiment part 3: neutral description

Answer 15

base rate is still ignore

Question 16

doctors confuse P(M+/C) and P(C/M+) because of

Answer 16

representativeness heuristic, a person with a positive mammogram is more similar to a person with cancer than to a person without cancer