Unbiased estimate Meaning

Hi Mentors,

what does it mean unbiased estimate the word ? can u please explain ?

have a separate test set you can use to get an unbiased estimate of how it was doing before you ship it,

Here’s how a NN is built:

  1. NN is fit on the training data.
  2. Choice of hyperparameters is guided by the dev set.

When having just train / dev sets (i.e. no test set), the final reported performance on dev set is optimistic since this data was used to adjust the hyperparameters.

Having a 3rd split of data i.e. test set to evaluate the final performance of the model is a good practice since the NN has never seen this split before and so gives an unbiased estimate of model performance.