I am trying to set up my data to work in the mlogit package in R
I have a dataframe created with the following code:
id <- 1:10
id <- rep(id, each=5)
site <- c("site1", "site2", "site3", "site4", "site5")
choice <- c("site3", "site5", "site1", "site4", "site2",
"site4", "site3", "site5", "site2", "site1")
df <- cbind(id, site)
I want to create a binary variable that indicates site choice for every value of id. As the id variable is a repeated sequence, the new indicator variable needs to be 0 for every row except the one in which "site" is equivalent to the relevant value of "choice". For id == 1, this will be the first element of the "choice" vector. For id == 2, it will be the 2nd element of the choice vector and so on.
A final dataframe with the variable included should look like this:
id site indicator
[1,] "1" "site1" "0"
[2,] "1" "site2" "0"
[3,] "1" "site3" "1"
[4,] "1" "site4" "0"
[5,] "1" "site5" "0"
[6,] "2" "site1" "0"
[7,] "2" "site2" "0"
[8,] "2" "site3" "0"
[9,] "2" "site4" "0"
[10,] "2" "site5" "1"
[11,] "3" "site1" "1"
[12,] "3" "site2" "0"
[13,] "3" "site3" "0"
[14,] "3" "site4" "0"
[15,] "3" "site5" "0"
[16,] "4" "site1" "0"
[17,] "4" "site2" "0"
[18,] "4" "site3" "0"
[19,] "4" "site4" "1"
[20,] "4" "site5" "0"
[21,] "5" "site1" "0"
[22,] "5" "site2" "1"
[23,] "5" "site3" "0"
[24,] "5" "site4" "0"
[25,] "5" "site5" "0"
[26,] "6" "site1" "0"
[27,] "6" "site2" "0"
[28,] "6" "site3" "0"
[29,] "6" "site4" "1"
[30,] "6" "site5" "0"
[31,] "7" "site1" "0"
[32,] "7" "site2" "0"
[33,] "7" "site3" "1"
[34,] "7" "site4" "0"
[35,] "7" "site5" "0"
[36,] "8" "site1" "0"
[37,] "8" "site2" "0"
[38,] "8" "site3" "0"
[39,] "8" "site4" "0"
[40,] "8" "site5" "1"
[41,] "9" "site1" "0"
[42,] "9" "site2" "1"
[43,] "9" "site3" "0"
[44,] "9" "site4" "0"
[45,] "9" "site5" "0"
[46,] "10" "site1" "1"
[47,] "10" "site2" "0"
[48,] "10" "site3" "0"
[49,] "10" "site4" "0"
[50,] "10" "site5" "0"
I have attempted this many times and cannot figure it out nor can I find a relevant answer online.
Thanks in advance :)
As Akrun suggested, use data.frame to define df:
df <- data.frame(id, site)
Then do:
df$indicator <- (df$site == choice[df$id])*1
The *1 will convert the T/F result to 1's and 0's
Result:
id site indicator
1 1 site1 0
2 1 site2 0
3 1 site3 1
4 1 site4 0
5 1 site5 0
6 2 site1 0
7 2 site2 0
8 2 site3 0
9 2 site4 0
10 2 site5 1
11 3 site1 1
12 3 site2 0
13 3 site3 0
14 3 site4 0
15 3 site5 0
16 4 site1 0
17 4 site2 0
18 4 site3 0
19 4 site4 1
20 4 site5 0
21 5 site1 0
22 5 site2 1
23 5 site3 0
24 5 site4 0
25 5 site5 0
26 6 site1 0
27 6 site2 0
28 6 site3 0
29 6 site4 1
30 6 site5 0
31 7 site1 0
32 7 site2 0
33 7 site3 1
34 7 site4 0
35 7 site5 0
36 8 site1 0
37 8 site2 0
38 8 site3 0
39 8 site4 0
40 8 site5 1
41 9 site1 0
42 9 site2 1
43 9 site3 0
44 9 site4 0
45 9 site5 0
46 10 site1 1
47 10 site2 0
48 10 site3 0
49 10 site4 0
50 10 site5 0
If you want strings instead of numbers or factors use as.character on the column you want to convert