Add welfare component

src/MimiFUND.jl

@@ -39,6 +39,7 @@ include("components/ImpactWaterResourcesComponent.jl")
 include("components/ImpactSeaLevelRiseComponent.jl")
 include("components/ImpactAggregationComponent.jl")
 include("components/VslVmorbComponent.jl")
+include("components/WelfareComponent.jl")
 
 export
     getfund # a function that returns a version of fund allowing for different user specifications
@@ -101,6 +102,7 @@ function get_model(; nsteps = default_nsteps, datadir = default_datadir, params
     add_comp!(m, impactwaterresources)
     add_comp!(m, impactsealevelrise)
     add_comp!(m, impactaggregation)
+    add_comp!(m, welfare)
 
     # ---------------------------------------------
     # Connect parameters to variables
@@ -242,6 +244,9 @@ function get_model(; nsteps = default_nsteps, datadir = default_datadir, params
     connect_param!(m, :impactaggregation, :wetcost, :impactsealevelrise, :wetcost)
     connect_param!(m, :impactaggregation, :leavecost, :impactsealevelrise, :leavecost)
 
+    connect_param!(m, :welfare, :populationin1, :population, :populationin1)
+    connect_param!(m, :welfare, :consumption, :socioeconomic, :consumption)
+
     # ---------------------------------------------
     # Set leftover parameters
     # ---------------------------------------------

src/components/WelfareComponent.jl

@@ -0,0 +1,49 @@
+func_U(c, γ) = γ==1.0 ? log(c) : c^(1-γ)/(1-γ)
+func_inv_U(u, γ) = γ==1.0 ? exp(u) : (u*(1-γ))^(1/(1-γ))
+func_V(c, η) = η==1.0 ? log(c) : c^(1-η)/(1-η)
+
+@defcomp welfare begin
+    regions = Index()
+
+    prtp = Parameter(default=0.015)
+    temporal_inequality_aversion = Parameter(default=1.5)
+    regional_inequality_aversion = Parameter(default=0.)
+
+    start_timeperiod::Int = Parameter(default=2020)
+
+    populationin1 = Parameter(index=[time,regions])
+    consumption = Parameter(index=[time,regions])
+
+    c_ede = Variable(index=[time])
+
+    welfare = Variable(index=[time])
+    marginal_welfare = Variable(index=[time, regions])
+    cum_welfare = Variable(index=[time])
+
+
+    function run_timestep(p, v, d, t)
+        year = gettime(t)
+
+        if year >= p.start_timeperiod
+            global_population = sum(p.populationin1[t,r] for r in d.regions)
+
+            c_ede = 0.
+            for r in d.regions
+                c_ede += func_U(p.consumption[t,r] / p.populationin1[t,r], p.regional_inequality_aversion) * p.populationin1[t,r] / global_population
+            end
+            v.c_ede[t] = func_inv_U(c_ede, p.regional_inequality_aversion)
+
+            v.welfare[t] = global_population * func_V(v.c_ede[t], p.temporal_inequality_aversion) * 1.0/(1+p.prtp)^(year-p.start_timeperiod)
+
+            if year==p.start_timeperiod
+                v.cum_welfare[t] = v.welfare[t]
+            else
+                v.cum_welfare[t] = v.cum_welfare[t-1] + v.welfare[t]
+            end
+
+            for r in d.regions
+                v.marginal_welfare[t,r] = v.c_ede[t]^(p.regional_inequality_aversion-p.temporal_inequality_aversion) * (p.consumption[t,r] / p.populationin1[t,r])^(-p.regional_inequality_aversion) * 1.0/(1+p.prtp)^(year-p.start_timeperiod)
+            end            
+        end
+    end
+end