Custom loss function in Keras for weighting missclassified samples












0















Assume that y_true and y_pred are in [-1,1]. I want a weighted mean-square-error loss function, in which the loss for samples that are positive in the y_true and negative in y_pred or vice versa are weighted by exp(alpha). Here is my code:



import keras.backend as K
alpha = 1.0
def custom_loss(y_true, y_pred):
se = K.square(y_pred-y_true)
true_label = K.less_equal(y_true,0.0)
pred_label = K.less_equal(y_pred,0.0)
return K.mean(se * K.exp(alpha*K.cast(K.not_equal(true_label,pred_label), tf.float32)))


And here is a plot of this loss function. Different curves are for different values for y_true.
enter image description here



I want to know:




  • Whether this is a valid loss function, since it is not differentiable in 0?

  • Is my code correct?










share|improve this question



























    0















    Assume that y_true and y_pred are in [-1,1]. I want a weighted mean-square-error loss function, in which the loss for samples that are positive in the y_true and negative in y_pred or vice versa are weighted by exp(alpha). Here is my code:



    import keras.backend as K
    alpha = 1.0
    def custom_loss(y_true, y_pred):
    se = K.square(y_pred-y_true)
    true_label = K.less_equal(y_true,0.0)
    pred_label = K.less_equal(y_pred,0.0)
    return K.mean(se * K.exp(alpha*K.cast(K.not_equal(true_label,pred_label), tf.float32)))


    And here is a plot of this loss function. Different curves are for different values for y_true.
    enter image description here



    I want to know:




    • Whether this is a valid loss function, since it is not differentiable in 0?

    • Is my code correct?










    share|improve this question

























      0












      0








      0








      Assume that y_true and y_pred are in [-1,1]. I want a weighted mean-square-error loss function, in which the loss for samples that are positive in the y_true and negative in y_pred or vice versa are weighted by exp(alpha). Here is my code:



      import keras.backend as K
      alpha = 1.0
      def custom_loss(y_true, y_pred):
      se = K.square(y_pred-y_true)
      true_label = K.less_equal(y_true,0.0)
      pred_label = K.less_equal(y_pred,0.0)
      return K.mean(se * K.exp(alpha*K.cast(K.not_equal(true_label,pred_label), tf.float32)))


      And here is a plot of this loss function. Different curves are for different values for y_true.
      enter image description here



      I want to know:




      • Whether this is a valid loss function, since it is not differentiable in 0?

      • Is my code correct?










      share|improve this question














      Assume that y_true and y_pred are in [-1,1]. I want a weighted mean-square-error loss function, in which the loss for samples that are positive in the y_true and negative in y_pred or vice versa are weighted by exp(alpha). Here is my code:



      import keras.backend as K
      alpha = 1.0
      def custom_loss(y_true, y_pred):
      se = K.square(y_pred-y_true)
      true_label = K.less_equal(y_true,0.0)
      pred_label = K.less_equal(y_pred,0.0)
      return K.mean(se * K.exp(alpha*K.cast(K.not_equal(true_label,pred_label), tf.float32)))


      And here is a plot of this loss function. Different curves are for different values for y_true.
      enter image description here



      I want to know:




      • Whether this is a valid loss function, since it is not differentiable in 0?

      • Is my code correct?







      python keras classification regression loss-function






      share|improve this question













      share|improve this question











      share|improve this question




      share|improve this question










      asked Nov 20 '18 at 14:32









      HosseinHossein

      961615




      961615
























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