Change to negative log-likelihood.

climax/core/loss.py

@@ -85,13 +85,13 @@ class BernoulliGammaLoss(NaNLoss):
         # negative log-likelihood function of Bernoulli-Gamma distribution
 
         # Bernoulli contribution
-        loss = (1 - p_true) * torch.log(1 - p_pred + self.epsilon)
+        loss = - (1 - p_true) * torch.log(1 - p_pred + self.epsilon)
 
         # Gamma contribution
-        loss += p_true * (torch.log(p_pred + self.epsilon) + (gshape - 1) *
+        loss -= p_true * (torch.log(p_pred + self.epsilon) + (gshape - 1) *
                           torch.log(y_true + self.epsilon) -
                           y_true / (gscale + self.epsilon) -
                           gshape * torch.log(gscale + self.epsilon) -
                           torch.lgamma(gshape + self.epsilon))
 
-        return - self.reduce(loss)
+        return self.reduce(loss)