begin(model(fairheads)).
heads.
toss.
fair.
prob(0.45).
end(model(fairheads)).

begin(model(fairtails)).
tails.
toss.
fair.
prob(0.45).
end(model(fairtails)).

begin(model(biasedheads)).
heads.
toss.
biased.
prob(0.06).
end(model(biasedheads)).

begin(model(biasedtails)).
tails.
toss.
biased.
prob(0.04).
end(model(biasedtails)).