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# Statistics - Interpolation

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1. I think this is the right place to post an AS Statistics question?

Hi,

Interpolation wasn't explained to me at all by my teacher, he just expects us to know

Anyway, could someone please "use interpolation to find an estimate for the median wage"?

Its from this table:

If it were possible, could you give a step by step method?

I know I'm asking so much, but I would literally love you forever...

If you can't be bothered to do it, maybe a few hints.

Thanks everyone
2. It looks like the easiest way to tackle the question is by considering the cumulative distribution function (CDF). Then the given data would read: CDF(174) = 0, CDF(225)=4/65, CDF(300)=(4+8)/65, etc. Now you need to interpolate CDF and then find it's inverse from 0.5

Good luck
3. Now I have a better idea: lets denote by f the inverse of the CDF, then the given data is f(0)=174, f(4/65)=225, f(12/65)=300, etc. Now interpolate and calculate f(0.5).
4. (Original post by markmat)
Now I have a better idea: lets denote by f the inverse of the CDF, then the given data is f(0)=174, f(4/65)=225, f(12/65)=300, etc. Now interpolate and calculate f(0.5).
Cheers!

Give you rep tomorrow

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