Net selectivity is the remaining selectivity after deducting the amount of return require to justify not being fully diversified

NetSelectivity(Ra, Rb, Rf = 0, ...)

Arguments

Ra

an xts, vector, matrix, data frame, timeSeries or zoo object of asset returns

Rb

return vector of the benchmark asset

Rf

risk free rate, in same period as your returns

any other passthru parameters

Details

If net selectivity is negative the portfolio manager has not justified the loss of diversification $$Net selectivity = \alpha - d$$

where \(\alpha\) is the selectivity and \(d\) is the diversification

References

Carl Bacon, Practical portfolio performance measurement and attribution, second edition 2008 p.78

Examples

data(portfolio_bacon) print(NetSelectivity(portfolio_bacon[,1], portfolio_bacon[,2])) #expected -0.017
#> portfolio.monthly.return.... #> portfolio.monthly.return.... -0.0178912
data(managers) print(NetSelectivity(managers['1996',1], managers['1996',8]))
#> HAM1 #> HAM1 0.01333906
print(NetSelectivity(managers['1996',1:5], managers['1996',8]))
#> HAM1 HAM2 HAM3 HAM4 HAM5 #> Net Selectivity (Risk free = 0) 0.01333906 NA 0.1745397 -0.03249043 NA