add Beta Bernoulli test, issue #11

Author: trappmartin

src/distfunctions.jl

@@ -85,7 +85,7 @@ function add!(d::DirichletMultinomial, X::SparseVector{Int, Int})
     d.dirty = true
 end
 
-function add!(d::BetaBernoulli, X::Integer)
+function add!(d::BetaBernoulli, X::Bool)
 	d.successes += X
 	d.n += 1
 end
@@ -261,8 +261,8 @@ function posteriorParameters(d::NormalNormal)
 end
 
 function posteriorParameters(d::BetaBernoulli)
-	α = d.α + d.successes
-	β = d.β + d.n - d.successes
+	α = d.α0 + d.successes
+	β = d.β0 + d.n - d.successes
 	return (α, β)
 end
 

test/distributionTests.jl

@@ -99,4 +99,42 @@ using LinearAlgebra
     @test β == β0
   end
 
+  @testset "Beta-Bernoulli" begin
+    
+    # prior
+    α0 = 1.0
+    β0 = 1.0
+
+    # data
+    x = Bool[0, 1, 0, 0, 1]
+    N = length(x)
+
+    # distribution
+    d = BetaBernoulli(α0 = α0, β0 = β0)
+
+    # test prior
+    (α, β) = BayesianNonparametrics.posteriorParameters(d)
+
+    @test α == α0
+    @test β == β0
+
+    # add data
+    BayesianNonparametrics.add!(d, x)
+
+    # test posterior paramters
+    (α, β) = BayesianNonparametrics.posteriorParameters(d)
+
+    @test α == α0 + sum(x)
+    @test β == β0 + (N - sum(x)) 
+
+    # remove data
+    BayesianNonparametrics.remove!(d, x)
+
+    # test prior
+    (α, β) = BayesianNonparametrics.posteriorParameters(d)
+
+    @test α == α0
+    @test β == β0
+  end
+
 end