conf_int(method='bca') scaler fix.

Author: esvhd

arch/bootstrap/base.py

@@ -462,6 +462,7 @@ def conf_int(self, func, reps=1000, method='basic', size=0.95, tail='two',
                         raise RuntimeError(message.format(jk_var=denom))
                     a = numer / denom
                     a = np.atleast_1d(a)
+                    a = a[:, None]
                 else:
                     a = 0.0