[Tune] [PB2] Correct pb2's beta_t parameter implementation (ray-proje…

…ct#28342)
justinvyu · Sep 14, 2022 · dfdfda0 · dfdfda0
1 parent e989f3e
commit dfdfda0
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/python/ray/tune/schedulers/pb2_utils.py b/python/ray/tune/schedulers/pb2_utils.py
@@ -98,7 +98,7 @@ def UCB(m, m1, x, fixed, kappa=0.5):
 
     c1 = 0.2
     c2 = 0.4
-    beta_t = c1 * np.log(c2 * m.X.shape[0])
+    beta_t = c1 + max(0, np.log(c2 * m.X.shape[0]))
     kappa = np.sqrt(beta_t)
 
     xtest = np.concatenate((fixed.reshape(-1, 1), np.array(x).reshape(-1, 1))).T