R 对具有多个列的两个数据帧列表执行多个双样本t检验
我有两个列表,每个列表有四个数据帧。两个列表(“loc_列表_未来”和“loc_列表_2019”)中的数据框有33列:“年”,然后是32个不同气候模型的平均降水量值 loc_list_future中的数据框如下所示,但共有32个模型列,数据将进入2059年:R 对具有多个列的两个数据帧列表执行多个双样本t检验,r,loops,statistics,t-test,R,Loops,Statistics,T Test,我有两个列表,每个列表有四个数据帧。两个列表(“loc_列表_未来”和“loc_列表_2019”)中的数据框有33列:“年”,然后是32个不同气候模型的平均降水量值 loc_list_future中的数据框如下所示,但共有32个模型列,数据将进入2059年: Year Model 1 Model 2 Model 3 ...Model 32 2020 714.1101 686.5888 1048.4274 2021 1018.0095
Year Model 1 Model 2 Model 3 ...Model 32
2020 714.1101 686.5888 1048.4274
2021 1018.0095 766.9161 514.2700
2022 756.7066 902.2542 906.2877
2023 906.9675 919.5234 647.6630
2024 767.4008 861.1275 700.2612
2025 876.1538 738.8370 664.3342
2026 781.5092 801.2387 743.8965
2027 876.3522 819.4323 675.3022
2028 626.9468 927.0774 696.1884
2029 752.4084 824.7682 835.1566
...
2059
2019年loc_列表中的数据帧的年份范围为2006-2019年,但在其他方面看起来相同
每个数据框代表一个地理位置,两个列表具有相同的四个位置,但一个列表用于2006-2019年的值,另一个用于未来的值
我想运行两个样本t检验,将2006-19年的值与每个位置每个模型的未来值进行比较
我有另一个列表(loc_list_OBS),其中数据帧只有两列“Year”和“Mean_Precip”(这是不基于模型的观测数据,这就是为什么Mean Precip只有一列)。我有代码(见下文)将针对未来数据(loc_list_future)对观测数据(loc_list_OBS)运行两个样本t测试,但我不确定如何更改此代码以对两个列表(每个列表有32个模型)运行t-tests
myfun <- function(x,y)
{
OBS_Data <- x$Mean_Precip
#Empty list
List <- list()
#Now loop
for(i in 2:dim(y)[2])
{
#Label
val <- names(y[,i,drop=F])
Future_Data <- y[,i]
#Test
test <- t.test(OBS_Data, Future_Data, alternative = "two.sided")
#Save
List[[i-1]] <- test
names(List)[i-1] <- val
}
return(List)
}
t.stat <- mapply(FUN = myfun,x=loc_list_OBS,y=loc_list_future, SIMPLIFY = FALSE)
myfun我建议下一种方法。我创建了与您所拥有的类似的虚拟数据。下面是代码:
#Data before
dfb <- structure(list(Year = 2010:2019, Model.1 = c(614.1101, 918.0095,
656.7066, 806.9675, 667.4008, 776.1538, 681.5092, 776.3522, 526.9468,
652.4084), Model.2 = c(586.5888, 666.9161, 802.2542, 819.5234,
761.1275, 638.837, 701.2387, 719.4323, 827.0774, 724.7682), Model.3 = c(948.4274,
414.27, 806.2877, 547.663, 600.2612, 564.3342, 643.8965, 575.3022,
596.1884, 735.1566)), class = "data.frame", row.names = c(NA,
-10L))
#Data after
dfa <- structure(list(Year = 2020:2029, Model.1 = c(714.1101, 1018.0095,
756.7066, 906.9675, 767.4008, 876.1538, 781.5092, 876.3522, 626.9468,
752.4084), Model.2 = c(686.5888, 766.9161, 902.2542, 919.5234,
861.1275, 738.837, 801.2387, 819.4323, 927.0774, 824.7682), Model.3 = c(1048.4274,
514.27, 906.2877, 647.663, 700.2612, 664.3342, 743.8965, 675.3022,
696.1884, 835.1566)), class = "data.frame", row.names = c(NA,
-10L))
#Data for lists
L.before <- list(df1=dfb,df2=dfb,df3=dfb,df4=dfb)
L.after <- list(df1=dfa,df2=dfa,df3=dfa,df4=dfa)
让我知道这是否对您有效!是的,这非常有效!再次感谢您,鸭子!我非常感谢您的帮助。
#Function
myfun <- function(x,y)
{
#Create empty list
List <- list()
#Loop
for(i in 2:dim(x)[2])
{
name <- names(x[,i,drop=F])
before <- x[,i]
after <- y[,i]
#Test
test <- t.test(before, after, alternative = "two.sided")
#Save
List[[i-1]] <- test
names(List)[i-1] <- name
}
return(List)
}
#Apply
t.stat <- mapply(FUN = myfun,x=L.before,y=L.after, SIMPLIFY = FALSE)
t.stat[[1]]
$Model.1
Welch Two Sample t-test
data: before and after
t = -1.9966, df = 18, p-value = 0.06122
alternative hypothesis: true difference in means is not equal to 0
95 percent confidence interval:
-205.224021 5.224021
sample estimates:
mean of x mean of y
707.6565 807.6565
$Model.2
Welch Two Sample t-test
data: before and after
t = -2.8054, df = 18, p-value = 0.0117
alternative hypothesis: true difference in means is not equal to 0
95 percent confidence interval:
-174.88934 -25.11066
sample estimates:
mean of x mean of y
724.7764 824.7764
$Model.3
Welch Two Sample t-test
data: before and after
t = -1.4829, df = 18, p-value = 0.1554
alternative hypothesis: true difference in means is not equal to 0
95 percent confidence interval:
-241.67613 41.67613
sample estimates:
mean of x mean of y
643.1787 743.1787