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This post will be about comparing a volatility signal using three different variations of implied volatility indices to predict when to enter a short volatility position.

In volatility trading, there are three separate implied volatility indices that have a somewhat long history for trading–the VIX (everyone knows this one), the VXV (more recently changed to be called the VIX3M), which is like the VIX, except for a three-month period), and the VXMT, which is the implied six-month volatility period.

This relationship gives investigation into three separate implied volatility ratios: VIX/VIX3M (aka VXV), VIX/VXMT, and VIX3M/VXMT, as predictors for entering a short (or long) volatility position.

So, let’s get the data.

require(quantmod)
require(PerformanceAnalytics)
require(TTR)
require(data.table)

destfile="vxvData.csv")
destfile="vxmtData.csv")

VIXdates <- VIX\$Date
VIX\$Date <- NULL; VIX <- xts(VIX, order.by=as.Date(VIXdates, format = '%m/%d/%Y'))

vxv <- xts(read.zoo("vxvData.csv", header=TRUE, sep=",", format="%m/%d/%Y", skip=2))
vxmt <- xts(read.zoo("vxmtData.csv", header=TRUE, sep=",", format="%m/%d/%Y", skip=2))

destfile="longXIV.txt")

xivRets <- Return.calculate(Cl(xiv))

One quick strategy to investigate is simple–the idea that the ratio should be below 1 (I.E. contango in implied volatility term structure) and decreasing (below a moving average). So when the ratio will be below 1 (that is, with longer-term implied volatility greater than shorter-term), and the ratio will be below its 60-day moving average, the strategy will take a position in XIV.

Here’s the code to do that.

stratStats
function(rets) {
stats <- rbind(table.AnnualizedReturns(rets), maxDrawdown(rets))
stats[5,] <- stats[1,]/stats[4,]
stats[6,] <- stats[1,]/UlcerIndex(rets)
rownames(stats)[4] <- "Worst Drawdown"
rownames(stats)[5] <- "Calmar Ratio"
rownames(stats)[6] <- "Ulcer Performance Index"
return(stats)
}

maShort <- SMA(vixVix3m, 60)
maMed <- SMA(vixVxmt, 60)
maLong <- SMA(vix3mVxmt, 60)

sigShort <- vixVix3m < 1 & vixVix3m < maShort
sigMed <- vixVxmt < 1 & vixVxmt < maMed
sigLong <- vix3mVxmt < 1 & vix3mVxmt < maLong

retsShort <- lag(sigShort, 2) * xivRets
retsMed <- lag(sigMed, 2) * xivRets
retsLong <- lag(sigLong, 2) * xivRets

compare <- na.omit(cbind(retsShort, retsMed, retsLong))
colnames(compare) <- c("Short", "Medium", "Long")
charts.PerformanceSummary(compare)
stratStats(compare)

With the following performance:

> stratStats(compare)
Short    Medium     Long
Annualized Return         0.5485000 0.6315000 0.638600
Annualized Std Dev        0.3874000 0.3799000 0.378900
Annualized Sharpe (Rf=0%) 1.4157000 1.6626000 1.685600
Worst Drawdown            0.5246983 0.5318472 0.335756
Calmar Ratio              1.0453627 1.1873711 1.901976
Ulcer Performance Index   3.7893478 4.6181788 5.244137

In other words, the VIX3M/VXMT sports the lowest drawdowns (by a large margin) with higher returns.

So, when people talk about which implied volatility ratio to use, I think this offers some strong evidence for the longer-out horizon as a predictor for which implied vol term structure to use. It’s also why it forms the basis of my subscription strategy.