Funnel Asymmetry

Problem

Split studies at the median standard error (the k//2 smallest versus the rest) and return the difference in fixed-effect pooled means (small-SE group minus large-SE group). Return 0.0 when fewer than two studies are given, any se <= 0, or a split group is empty.

Hint

If small studies report larger effects, the funnel leans to one side.

Test cases

case 1

in: [[1,0.8,1.2,0.5],[0.1,0.2,0.15,0.3]]

expected: 0.3538461538461537

case 2

in: [[1,1],[0.1,0.2]]

expected: 0

case 3

in: [[0.5,0.5,0.5,0.5],[0.1,0.2,0.3,0.4]]

expected: 0

case 4

in: [[1],[0.1]]

expected: 0

case 5

in: [[2,1.5],[0.1,0.4]]

expected: 0.5

Starter codePython

def funnel_asymmetry(yi, sei):
    # Your code here
    pass

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