以下是我执行多项式线性回归的步骤。
> z<-read.table("2008 Racedata.txt", header=TRUE, sep="\t", row.names=NULL)
> head(z)
datekey raceno horseno place winner draw winodds log_odds jwt hwt
1 2008091501 1 8 1 1 2 12.0 2.484907 128 1170
2 2008091501 1 11 2 0 3 8.6 2.151762 123 1135
3 2008091501 1 6 3 0 5 7.0 1.945910 127 1114
4 2008091501 1 12 4 0 10 23.0 3.135494 123 1018
5 2008091501 1 14 5 0 4 11.0 2.397895 113 1027
6 2008091501 1 5 6 0 14 50.0 3.912023 131 972
> x<-mlogit.data(z,choice="winner",shape="long",id.var="datekey",alt.var="horseno")
Error in `row.names<-.data.frame`(`*tmp*`, value = c("1.8", "1.11", "1.6", :
duplicate 'row.names' are not allowed
In addition: Warning message:
non-unique values when setting 'row.names': ‘10.2’, ‘10.4’, ‘10.8’,
‘100.7’, ‘101.12’, ‘102.1’, ‘102.3’, ‘103.2’, ‘103.4’,
‘103.6’, ‘104.12’, ‘104.3’, ‘104.9’, ‘105.1’, ‘105.5’,
‘105.6’, ‘105.8’, ‘106.11’, ‘106.12’, ‘106.13’, ‘106.7’,
‘107.10’, ‘107.14’, ‘107.3’, ‘108.12’, ‘108.2’, ‘108.6’,
‘108.9’, ‘109.1’, ‘109.14’, ‘109.7’, ‘11.12’, ‘11.5’,
‘11.9’, ‘110.2’, ‘110.3’, ‘110.4’, ‘110.9’, ‘111.1’,
‘111.7’, ‘112.12’, ‘112.3’, ‘112.6’, ‘112.8’, ‘113.10’,
‘113.13’, ‘113.7’, ‘114.12’, ‘114.2’, ‘114.9’, ‘115.10’,
‘115.13’, ‘115.5’, ‘116.11’, ‘116.6’, ‘117.14’, ‘117.3’,
‘117.7’, ‘118.1’, ‘118.13’, ‘118.2’, ‘118.9’, ‘119.10’,
‘119.5’, ‘119.6’, ‘119.8’, ‘12.1’, ‘12.10’, ‘12.3’,
‚Äò12.6‚Äô, ‚Äò120.2‚Äô, ‚Äò120.4‚Äô, ‚Äò120.7‚ [... truncated]
>
我在这里错过了什么步骤？为什么row.names中有重复项？
谢谢， 沃尔特
答案 0 :(得分：0)
两个问题。
您似乎遇到编码问题，因为我们在该错误消息中看到了很多变音符号和重音符号。此外，我想知道该datekey列是否已转换为因子类？
在这种情况下，它指的是构造新对象x的row.names属性时出错。如果你这样做：
with( z, table( datekey, horseno) )
......你可能会在同一天看到一匹有多个参赛作品的马。
实际上没有重复的datekey x horseno组合。更改为horseno和datekey的因子，然后将“long”参数切换为“wide”会产生无错误的结果：
z$datekey <- as.character(z$datekey)
z$horseno <- as.character(z$horseno)
x<-mlogit.data(z,choice="winner",shape="wide",id.var="datekey",alt.var="horseno")
str(x)
#----------
Classes ‘mlogit.data’ and 'data.frame': 18312 obs. of 11 variables:
$ datekey : Factor w/ 733 levels "2008091501","2008091502",..: 1 1 1 1 1 1 1 1 1 1 ...
$ raceno : int 1 1 1 1 1 1 1 1 1 1 ...
$ horseno : chr "0" "1" "0" "1" ...
$ place : int 1 1 2 2 3 3 4 4 5 5 ...
$ winner : logi FALSE TRUE TRUE FALSE TRUE FALSE ...
$ draw : int 2 2 3 3 5 5 10 10 4 4 ...
$ winodds : num 12 12 8.6 8.6 7 7 23 23 11 11 ...
$ log_odds: num 2.48 2.48 2.15 2.15 1.95 ...
$ jwt : int 128 128 123 123 127 127 123 123 113 113 ...
$ hwt : int 1170 1170 1135 1135 1114 1114 1018 1018 1027 1027 ...
$ chid : num 1 1 2 2 3 3 4 4 5 5 ...
- attr(*, "index")='data.frame': 18312 obs. of 3 variables:
..$ chid: Factor w/ 9156 levels "1","2","3","4",..: 1 1 2 2 3 3 4 4 5 5 ...
..$ alt : Factor w/ 2 levels "0","1": 1 2 1 2 1 2 1 2 1 2 ...
..$ id : Factor w/ 733 levels "2008091501","2008091502",..: 1 1 1 1 1 1 1 1 1 1 ...
- attr(*, "choice")= chr "winner"