quantile question
have a look at the online help file of ?quantile(); check also: x <- c(67.12, 64.51, 62.06, 55.45, 51.41, 43.78, 10.74, 10.14) sapply(1:9, function (i) quantile(x, c(0.05, 0.95), type = i)) I hope it helps. Best, Dimitris
ANJAN PURKAYASTHA wrote:
Hi, A simple quantile question: I need to calculate the 95% and 5% quantiles (aka percentiles) for the following data: 67.12 64.51 62.06 55.45 51.41 43.78 10.74 10.14 if I use the formula: 95% quantile point= 95 (8+1)/100, I get the 8.55th point as the 95% quantile. Which does not make too much sense as I have only 8 data points. The other option is to use (95*8)/100 = 7.6th data point (which can be found by interpolation between the 7th and 8th data points). Reportedly, the second formula is not too accurate. However in my case the first formula does not make much sense. Any advice? TIA, Anjan
Dimitris Rizopoulos Assistant Professor Department of Biostatistics Erasmus Medical Center Address: PO Box 2040, 3000 CA Rotterdam, the Netherlands Tel: +31/(0)10/7043478 Fax: +31/(0)10/7043014