The poly fits on logarithm of option prices are performed for each side
of the suggested cusp (specified by k.cusp
).
This utiility is used mainly to remove the market data noise for
the calculation of log-slope of option prices.
ecop.polyfit_option(k, V, k.cusp, k.new, degree.left = 6, degree.right = 6)
numeric, vector of log-strike
numeric, vectors of option prices
length-one numeric, the suggested cusp location
numeric, vector of log-strike to evaluate the poly fit
length-one numeric, specifying the degree of poly fit for the left tail
length-one numeric, specifying the degree of poly fit for the right tail
The state prices from the poly fit