I choose the number of MESA coefficients according to https://sepwww.stanford.edu/data/media/public/docs/sep134/jim2/paper.pdf For example, Code: $ perl -e 'my $numTradingDaysHw7thruHw0 = 100; my $numCoeff = int(2 * $numTradingDaysHw7thruHw0 / log (2 * $numTradingDaysHw7thruHw0)); print "numTradingDaysHw7thruHw0 $numTradingDaysHw7thruHw0 numCoeff $numCoeff\n";' numTradingDaysHw7thruHw0 100 numCoeff 37 And it's definitely not the holy grail.