Getting worse result using keras 2 than keras 1
Probably some default values that have changed from Keras 1.2.
You should check the default values for you 1.2 code, and set the same value for your new code.
I ran the same code (with the same data) on CPU first using keras 1.2.0 and then keras 2.0.3 in both codes keras is with TensorFlow backend and also I used sklearn for model selection, plus pandas to read data. 
I was surprised when I got the MSE(Mean squared error) of 42 using keras 2.0.3 and 21 using keras 1.2.0. Can someone pls explain to me why this is happening? Why I am getting more error using keras 2? Thanks
PS. This result is after editing the code to keras 2 standard. for example in Dense I change keras 1 code to keras 2 standard.