繪製迴歸線與格子

Question

我在這裏有點麻煩，請幫助我。 我有這個數據

set.seed(4) 
mydata <- data.frame(var = rnorm(100), 
        temp = rnorm(100), 
        subj = as.factor(rep(c(1:10),5)), 
        trt = rep(c("A","B"), 50)) 

而這種模式適合他們

lm <- lm(var ~ temp * subj, data = mydata) 

我想格子繪製的結果和擬合迴歸線的，預測與我的模型，通過他們。要做到這一點，我用這種方法，概括「對於電力用戶萊迪思技巧」由D.薩卡

temp_rng <- range(mydata$temp, finite = TRUE) 

grid <- expand.grid(temp = do.breaks(temp_rng, 30), 
        subj = unique(mydata$subj), 
        trt = unique(mydata$trt)) 

model <- cbind(grid, var = predict(lm, newdata = grid)) 

orig <- mydata[c("var","temp","subj","trt")] 

combined <- make.groups(original = orig, model = model) 


xyplot(var ~ temp | subj, 
     data = combined, 
     groups = which, 
     type = c("p", "l"), 
     distribute.type = TRUE 
     ) 

到目前爲止一切都很好，但我也想將填充顏色分配給數據兩個處理點分別爲trt=1和trt=2。

所以我寫這一段代碼，工作正常，但是當它涉及到繪製迴歸線，似乎型不被面板功能的認可......

my.fill <- c("black", "grey") 

plot <- with(combined, 
     xyplot(var ~ temp | subj, 
       data = combined, 
       group = combined$which, 
       type = c("p", "l"), 
       distribute.type = TRUE, 
       panel = function(x, y, ..., subscripts){ 
        fill <- my.fill[combined$trt[subscripts]] 
        panel.xyplot(x, y, pch = 21, fill = my.fill, col = "black") 
        }, 
      key = list(space = "right", 
        text = list(c("trt1", "trt2"), cex = 0.8), 
        points = list(pch = c(21), fill = c("black", "grey")), 
        rep = FALSE) 
        ) 
    ) 
plot 

我以前也嘗試過移動式和內panel.xyplot分佈類型，以及在它panel.xyplot任子集劃分的數據這樣

plot <- with(combined, 
     xyplot(var ~ temp | subj, 
       data = combined, 
       panel = function(x, y, ..., subscripts){ 
        fill <- my.fill[combined$trt[subscripts]] 
        panel.xyplot(x[combined$which=="original"], y[combined$which=="original"], pch = 21, fill = my.fill, col = "black") 
        panel.xyplot(x[combined$which=="model"], y[combined$which=="model"], type = "l", col = "black") 
        }, 
      key = list(space = "right", 
        text = list(c("trt1", "trt2"), cex = 0.8), 
        points = list(pch = c(21), fill = c("black", "grey")), 
        rep = FALSE) 
        ) 
    ) 
plot 

但沒有成功。

任何人都可以幫助我得到預測值繪製爲一條線，而不是點？

Answer 1

這可能是爲latticeExtra包工作。

library(latticeExtra) 
p1 <- xyplot(var ~ temp | subj, data=orig, panel=function(..., subscripts) { 
    fill <- my.fill[combined$trt[subscripts]] 
    panel.xyplot(..., pch=21, fill=my.fill, col="black") 
}) 
p2 <- xyplot(var ~ temp | subj, data=model, type="l") 
p1+p2 

我不知道發生了什麼事情在你的第一次嘗試，但一個與標不工作，因爲x和y是SUBJ的數據的一個子集，因此子集他們使用基於combined的矢量將不會按照您認爲的方式工作。試試這個。

xyplot(var ~ temp | subj, groups=which, data = combined, 
     panel = function(x, y, groups, subscripts){ 
     fill <- my.fill[combined$trt[subscripts]] 
     g <- groups[subscripts] 
     panel.points(x[g=="original"], y[g=="original"], pch = 21, 
         fill = my.fill, col = "black") 
     panel.lines(x[g=="model"], y[g=="model"], col = "black") 
     }, 
     key = list(space = "right", 
     text = list(c("trt1", "trt2"), cex = 0.8), 
     points = list(pch = c(21), fill = c("black", "grey")), 
     rep = FALSE) 
     ) 

Answer 2

可能更容易簡單地使用panel.lmline功能上只是你的原始數據：

xyplot(var ~ temp | subj, 
     data = orig, 
     panel = function(x,y,...,subscripts){ 
      fill <- my.fill[orig$trt[subscripts]] 
      panel.xyplot(x, y, pch = 21, fill = my.fill,col = "black") 
      panel.lmline(x,y,col = "salmon") 
     }, 
     key = list(space = "right", 
        text = list(c("trt1", "trt2"), cex = 0.8), 
        points = list(pch = c(21), fill = c("black", "grey")), 
        rep = FALSE) 
) 

Answer 3

這可能是微不足道的，但你可以嘗試：

xyplot(... , type=c("p","l","r")) 

「p補充說：」點「l」他們用虛線連接，「r」適合通過你的數據的線性模型。僅顯示type="r"僅繪製迴歸線而不顯示數據點。