MediumNLPnlp-130

Witten-Bell Lambda

Problem

Return the Witten-Bell interpolation weight lambda = N1 / (N + N1), where N is the total count and N1 is the number of distinct event types in counts.

Return 0.0 when both N and N1 are 0.

Hint

N is the total event count and N1 is the number of distinct events.

Test cases

case 1

in: [[1,1,2]]

expected: 0.42857142857142855

case 2

in: [[]]

expected: 0

case 3

in: [[0,0]]

expected: 1

case 4

in: [[5]]

expected: 0.16666666666666666

Starter codePython

def witten_bell_lambda(counts):
    # Your code here
    pass

4 test cases · run your code against them in the editor