GINI Coefficient Formula

Hello all, does anyone have any ideas on how the formula for the GINI coefficient could be expressed in Excel ΣiΣj(yi-yj)

In the formula, y refers to income and both i and j refer to households. Thus for instance if there were two households then to get ΣiΣj(yi-yj) first set i equal to one then do the single sum across the js. Then set i = 2 and do the single sum across the js. Sum the two sums, and you have it. This is equivalent to:

ΣiΣj(yi-yj) = |y1-y1| + |y1-y2| + |y2-y1| + |y2-y2|

I represents the total number of households (which is why you sum from i = 1 to I and also from j = 1 to I).

In my case I have 100 households.

Any help would be much appreciated.

what would this do?
I can't seem to get it to work on my excel sheet

ok here it is. thanks for your help.

essentially what I have to find out is the sum of the absolute differences of all possible pairs...

I'm not sure if this is the correct method....my prof says it requires relative and absolute references:

"It is in fact quite straightforward if you make use of the relative and absolute cell references - which I covered in the Excel tutorial. Again, take this step by step on a 2*2 example."

this is just the numerator of a larger formula where the denominator is: 2*Isquared*mean where I is the number of observations...it should yield a number between 0 and 1, the gini coefficient.

im having a little trouble with this too and any help would be awesome! how we would sum the absolute values of the differences of all possible pairs out of 100.basically i need a function in excel for: ΣiΣj(yi-yj) = |y1-y1| + |y1-y2| + |y2-y1| + |y2-y2|

If you have difficulties with shgs' advice, then ask your prof!!!

I'm not sure if this is the correct method....my prof says it requires relative and absolute references

I'm ****** sure he will know better!!!

P.S. I'll probably get an infraction penalty for this, but after a few pints, what the h****, advice is FREE.

my prof is useless

In case the problem is not solved yet. The answer is
=SUMPRODUCT(ABS(A2:A101 - TRANSPOSE(A2:A101)))/(COUNT(A2:A101)*2*SUM(A2:A101))

@ rchou
This thread is some 20 months old, I doubt if sdiazl will reply.
He/she is now probably doing Political Science!