It appears your code is not handling the “ham” class correctly.

Notice that all your output numbers are different, although the 0 value that Tom points out is particularly scary. An error in the third or fourth decimal place is not a rounding error: it’s a real error.

There aren’t really very many moving parts in the `prob_word_given_class`

function: are you sure your previous functions (e.g. `get_word_frequency`

) passed their tests and that your notebook is in a consistent state. Try this:

Kernel → Restart and Clear Output

Save

Cell → Run All

Now carefully look through and make sure everything earlier passes and take a look at the numbers you showed above again. I got pretty much exact matches for the expected values:

i still can’t understand what i should do

It’s also possible that you might be using an obsolete version of the notebook.

i think so how can i update the notebook?

Please check your personal messages for instructions.