REAL alpha ~ continuous_uniform(-1, 1)

ENTITY square, "models/simplebirds_spatial/squares.txt", "models/simplebirds_spatial/adjacency.txt"
{
	INTEGER northerness(1)
}

ENTITY bird, ""
{
}

ENTITY squarebird, "models/simplebirds_spatial/observations.txt", combines(square, bird)
{
	INTEGER q = SUM(&x)
	REAL p = EXP(alpha * northerness + q) / (1 + EXP(alpha * northerness + q))
	INTEGER x ~ user_bernoulli(p)
	INTEGER obs(*) ~ user_defined_points(x)
}