kmmoon100
2013-Nov-19 02:29 UTC
[R] How can I get seasonal variation table from generalized additive mixed models in R?
Hello everyone, I used a function called gamm in mgcv in R program to investigate seasonal variation of wind speed based on 13 years of measurement dataset. I would like to use this variation in my formula for my study but as I am new in R, it's extremely hard to find values on y-axis.. too many sub-directories of gamm values make me hard to find what directory was actually used for y-axis. My data set is like this below: time /day.of.year/ month /day.of.month /year / WindSpeed 1 1 7 24 2000 23.429 2 2 7 25 2000 29.170 3 3 7 26 2000 16.813 4 4 7 27 2000 15.271 5 5 7 28 2000 10.125 6 6 7 29 2000 13.938 7 7 7 30 2000 15.854 8 8 7 31 2000 10.438 9 9 8 1 2000 7.125 . . . . . . . . . . . . As time stamps are separated, I combined all of them first and then ran additive modelling to look at seasonal and yearly trends of 13 years of wind data. My R codes are described below: ballarat <- read.csv("ballarat seasonal daily.csv", header=TRUE, sep=",") ballarat1 <- within(ballarat, Date <- as.Date(paste(year, month, day.of.month, sep = "-"))) plot(WindSpeed ~ Date, data = ballarat1, type = "l") mod <- gamm(WindSpeed ~ s(day.of.year, bs = "cc") + s(time, bs "cr"), data = ballarat1, method = "REML", correlation = corAR1(form = ~ 1 | year), knots = list(day.of.year = c(0, 366))) summary(mod$gam) plot(mod$gam, pages = 1) http://i.stack.imgur.com/wU0AU.jpg>From the link page of trend graphs, You can see that average wind speed hasabout +- 2 km/hr variation. I would like to produce tables (two columns (first column: x axis values, second column: y axis (variations)) each day of year) of those two graphs. I assume I need to use gam.predict to get tables of the prediction? As I am new in R, I still can't understand how I can make it work even after reading description of ?gam.predict function. Could you please show me how to do it step by step? Regards, Kangmin. -- View this message in context: http://r.789695.n4.nabble.com/How-can-I-get-seasonal-variation-table-from-generalized-additive-mixed-models-in-R-tp4680710.html Sent from the R help mailing list archive at Nabble.com.