9 - Decision Making Flashcards
3 factors contributing to strength of an inductive argument
representativeness of observations
number of observations
quality of the evidence
judgement: affect heuristics
basing a judgement on how much dread one feels
Winkielman et al. (1997) - primed observers with a smiling face, a frowning face, or neutral polygon presented at about 4 milliseconds
participants were then asked to rate Chinese character on a scale of liking
ppts preferred the ideograph preceded with a smiling face as opposed to those preceded by a frowning face or neutral polygon
illusory correlation
a correlation between two events appears to exist, but either this is false or much weaker than assumed
may take the form of stereotypes
representativeness heuristics
the probability that A is a member of class B determined by how well properties of A resemble properties usually associated with class B
base rate
when only base rate is available, ppl will use this info
when descriptive info is available, ppl often disregard the base rate info, causing errors in reasoning
conjunction rule
probability of two events cannot be higher than the probability of the single constituents
violated conjunction rule
Tversky and Kahneman (1983):
85% chose statement 2
ppts influenced by repetitiveness heuristic
law of large numbers
+ study
the larger the no. of individuals randomly drawn from a population, the more representative the resulting group will be the entire population
Tversky and Kahneman 1974
smaller samples of numbers of individuals are less likely to be representative of general population
myside bias
tendency for people to generate and evaluate evidence and test their hypotheses in a way that is biased toward their own opinions and attitudes
errors occur when people let their own opinions and attitudes influence how they evaluate evidence needed to make decisions
myside bias study
Lord et al 1979
gave questionnaire to two groups, one in favour of capital punishment, one against
presented with descriptions of research studies into capital punishment
ppts rated articles - responses reflected attitudes they had at the start of the study - type of confirmation bias
confirmation bias
tendency to selectively look for info that conforms to our hypothesis and overlook info that argues against it
decisions: utility approach
given all the relevant info, ppl will make a decision that results in the maximum expected utility
utility often considered in monetary terms
advantages for utility approach
specific procedures to determine the best choice
problems for utility approach
not necessarily money, ppl find value in other things
many decisions dont maximize the probability of the best outcome
people often ignore optimum way of responding
Denes-Raj and Epstein’s 1994 jelly beans
ppts got money if they picked a red bean
bowl 1 - 1 red, 9 white
bowl 2 - 7 red 93 white
many ppts chose bowl with more red beans - felt they had better chance even tho probabilities against them
