Harroll C index, although video explanation clearly understandable, I found the assignment grader cell confusing

Hello Mentors of AI4M,

I would really appreciate if anyone can explain me the section of Harroll C-index codes. I have passed this assignment but I felt the codes are confusing or mismatching.

From what I understood when Course instructor Pranav explains first we need to find the permissible pairs and then the concordant pairs which is then used to find the C-index.

But the assignment section before the grader cell has the below explanation

Somehow that statement mentioned
ta = tb was censored and A was censored means A actually lived longer than B does certifies the statement.
Censored observations are subjects who either die of causes other than the disease of interest or are lost to follow-up.
So the statement A actually lived longer than B may or may not be true as it is censored due to unknown reason may be died or didn’t show up for followup.

So, the below statements could have been used ones and then created the permissible pair and then concordant.(I can’t share the code here as they are part of graded cell assignment)
1.check if at most one is censored
2. check if one is censored

The code applied for first statement as OR statement for events where as for second statement it was event that are not equal. Can’t this codes be made more simpler??

It is just a thought, as I felt stuck in this section due to confusion of permissible pair codes as I felt how Pranav explained was lot simpler than the codes used.


Hi Deepti,

As we discussed in depth, offline, thanks for your useful observation and suggestion. We could could put it up for future refreshes of course content.

Best Regards.