[R] How to get rid of extra areas on spatial data map

2010-04-16 Thread Changyou Sun
Hello All, I am using "sp" and "maps" libraries to have a map for some fire data. The region covered is Mississippi State in the US. Then I would like to add a layer of ecoregion on the top (omenrik layer from nationalatlas.gov). The problem is that the ecoregion layer is larger than the state bou

[R] garch estimation with exogenouse variables

2010-04-09 Thread Changyou Sun
Hello All, I need to estimate a GARCH model. The mean equation contains exogenous variables like Y = B * X + et. I understand the garch function in tseries package can handle univariate model, and garchFit in fGarch can handle ARMA specification. Is there any function that can handle exogenous var

[R] Package ismev, gpd.fit, and interpretation for statistics of extreme values

2010-01-31 Thread Changyou Sun
tion is related to calculating return levels. There are multiple fires on individual calendar days. Each year there are 2000 to 5000 fires. I am not sure how to specify the number of observations per year, i.e., the value of "npy" and which formulas should be used. Thank you for your h

Re: [R] navigation panel with help

2010-01-28 Thread Changyou Sun
, January 28, 2010 2:19 PM To: Changyou Sun Cc: r-help@r-project.org Subject: Re: [R] navigation panel with help On 28/01/2010 3:15 PM, Edwin Sun wrote: > All, > > I installed the lastest version of R 2.10.1. On the help page for a specific > function, it turns out that the vertica

[R] Duration model with sample selection (or selectivity)

2009-12-16 Thread Changyou Sun
Hello All, I am interested in estimating a duration model (also known as survival analysis or event-history analysis). I use an economic dataset. In economics terms, the model is "duration model with sample selection (or selectivity)." The time spell variable is only observed for a sample that mee

[R] ggplot legend for multiple time series

2009-12-01 Thread Changyou Sun
<- data.frame(year=1875:1972, level=LakeHuron) ggplot(huron, aes(year)) + geom_line(aes(y=level+5, colour="above")) + geom_line(aes(y=level-5, colour="below")) + scale_colour_manual("Direction", c("above"="black", "below&