UtilityModels.ExpectedUtility
— TypeExpectedUtility
ExpectedUtility
constructs a model object for expected utility theory
α
: utility curvature for gains
Constructor
ExpectedUtility(;α=.80)
UtilityModels.Gamble
— TypeGamble(;p=[.5,.5], v=[10.0,0.0])
Constructs a gamble object with probability vector p
and outcome vector v
.
Fields
p
: probability vectorv
: outcome vector
UtilityModels.ProspectTheory
— TypeProspectTheory(;α=.80, β=α, γg=.70, γl=γg, λ=2.25)
Constructs a model object for cummulative prospect theory. By default, parameters for utility curvature and probability weigting are equal gains and losses.
Fields
α=.80
: utility curvature for gainsβ=α
: utility curvature for lossesγg=.70
: probability weighting parameter for gainsγl=γg
: probability weighting parameter for lossesλ=2.25
: loss aversion parameter
References
Fennema, H., & Wakker, P. (1997). Original and cumulative prospect theory: A discussion of empirical differences. Journal of Behavioral Decision Making, 10(1), 53-64.
Tversky, A., & Kahneman, D. (1992). Advances in prospect theory: Cumulative representation of uncertainty. Journal of Risk and uncertainty, 5(4), 297-323.
UtilityModels.TAX
— TypeTAX(;δ=.80, β=.3, γ=.70)
Constructs a model object for transfer of attention exchange.
Fields
δ=1.0
: transfer of attention parameterγ=1.0
: probability weighting parameterβ=.70
: utility curvature
References
Birnbaum, M. H., & Chavez, A. (1997). Tests of theories of decision making: Violations of branch independence and distribution independence. Organizational Behavior and Human Decision Processes, 71(2), 161-194. Birnbaum, M. H. (2008). New paradoxes of risky decision making. Psychological Review, 115(2), 463.
UtilityModels.UtilityModel
— TypeUtilityModel
UtilityModel
is an abstract utility-based model object ````
UtilityModels.ValenceExpectancy
— TypeValenceExpectancy
ValenceExpectancy
constructs a model object for expected utility theory
υ
: a vector of expected utilitiesΔ
: learning rate whereΔ ∈ [0,1]
α
: utility shape parameter whereα > 0
λ
: loss aversion whereλ > 0
c
: temperature
Statistics.mean
— Methodmean(model::TAX, gamble::Gamble)
Computes mean utility for the TAX model
Arguments
model
: a model M <: UtilityModelgamble
: a gamble object
Statistics.mean
— Methodmean
mean
generic method for computing mean
model
: a model M <: UtilityModelgamble
: a gamble object
Function Signature
mean(model::UtilityModel, gamble::Gamble)
Statistics.std
— Methodstd(model::UtilityModel, gamble::Gamble)
std
a generic method for computing the standard deviation of the gamble
model
: a model M <: UtilityModelgamble
: a gamble object
Statistics.var
— Methodvar(model::UtilityModel, gamble::Gamble)
var
a generic method for computing the variance of the gamble
model
: a model M <: UtilityModelgamble
: a gamble object
UtilityModels._compute_weights
— Method_compute_weights(p, γ)
Computes decision weights based on cummulative outcomes
Arguments
p
: a probability vectorγ
: parameter that controls weighting of low and high probabilities
UtilityModels.compute_utility
— Methodcompute_utility
compute_utility
computes utility of gamble outcomes according to expected utility theory
model
: a model object for prospect theorygamble
: a gamble object
Function Signature
compute_utility(model::ExpectedUtility, gamble::Gamble)
UtilityModels.compute_utility
— Methodcompute_utility(model::ProspectTheory, gamble)
Computes utility of gamble outcomes according to prospect theory
Arguments
model
: a model object for prospect theorygamble
: a gamble object
UtilityModels.compute_utility
— Methodcompute_utility(model::TAX, gamble)
Computes utility of gamble outcomes according to TAX
Arguments
model
: a model object for TAXgamble
: a gamble object
UtilityModels.compute_utility
— Methodcompute_utility(model::ValenceExpectancy, outcomes::Vector)
compute_utility
computes utility of gamble outcomes according to expected utility theory
model
: a model object for prospect theorygamble
: a gamble object
Function Signature
compute_utility(model::ExpectedUtility, gamble::Gamble)
UtilityModels.compute_weights
— Methodcompute_weights(model::ProspectTheory, gamble::Gamble)
Computes decision weights based on cummulative outcomes
Arguments
model
: a model object for prospect theorygamble
: a gamble object
UtilityModels.compute_weights
— Methodcompute_weights(model::UtilityModel, gamble::Gamble)
compute_weights
a generic method for computing decision weights
model
: a model M <: UtilityModelgamble
: a gamble object
UtilityModels.sort!
— Methodsort!(model::UtilityModel, gamble)
sort!
a generic method for sorting gamble probabilities and values. The generic method does not sort the gambles
model
: a modelgamble
: a gamble object