title: Keras class weights
body: <p><code>keras</code> documentation is a little vague about <code>class_weight</code> parameter in <code>model.fit()</code>. I have a dataset with binary labels but it's instances per class are imbalanced. <code>Class 0</code> has <code>1000</code> instances while <code>class 1</code> has <code>15,000</code> instances. How would I set <code>class_weight</code> dictionary in this case? Would it be like <code>class_weight = {0: 0.07, 1: 0.93}</code> or there's some other method to calculate these values?</p>