I found this paper called: What Does Implied Volatility Skew Measure?http://papers.ssrn.com/sol3/papers.cfm? ... =1618602So far I've liked what I read, just wondering what other people have to say about this paper.Thanks,Akki

The problem of mesuring the skew is separated in two differents questions depending on who you are talking to :1/ Market practioneer : Here it's mainly a question of convention and you have to cope with this convention if you want to be understood. Each market has its uses and so Traders on Equity's options prefers to speak of the volatility linked to a pair Strike/Maturity (sometimes they can also use Moneyness/maturity whereas the FX Options trader will say the X-Delta Call's volatility or the X-Delta's put maturity with X varying from 10 to 50. But beware this last measure hides some particularities as it depends also on how you compute your Delta : Delta or Delta+Prime2/ Theoreticians : And there, a good measure can be effectively the scott mixon's which is the one used by FX Options traders. Nonetheless a better coverage of the subject is done by Rebonato in 'Volatiity And Correlation'.