Filtering a panel dataset in r - r

Question

I have a dataframe of this form
familyid memberid occupation panelid year
1 1 1 1 2000
1 2 1 1 2000
2 1 1 1 2000
2 2 2 1 2000
3 1 1 1 2000
3 2 1 1 2000
3 3 1 1 2000
1 1 2 2 2001
1 2 1 2 2001
2 1 2 2 2001
2 2 2 2 2001
3 1 1 2 2001
3 2 2 2 2001
3 3 2 2 2001
I want to filter this dataframe in order to get the following.
familyid memberid occupation panelid year
1 1 1 1 2000
2 1 1 1 2000
3 2 1 1 2000
3 3 1 1 2000
1 1 2 2 2001
2 1 2 2 2001
3 2 2 2 2001
3 3 2 2 2001
In words, I want to keep only the panel obs that present occupation==1 in year 2000 (panelid==1) and occupation==2 in year 2001 (panelid==2). Does anybody know how to do this? Many thank to everyone,
Marco

Answer 1

Here, we can group by 'familyid', 'memberid', filter based on any 'occupation' 1 and 'year' 2000 as well as any 'occupation' 2 and 'year' 2001
library(tidyverse)
df1 %>%
group_by(familyid, memberid) %>%
filter(any(occupation == 1 & year == 2000) & any(occupation == 2 & year == 2001))
# A tibble: 8 x 5
# Groups: familyid, memberid [4]
# familyid memberid occupation panelid year
# <int> <int> <int> <int> <int>
#1 1 1 1 1 2000
#2 2 1 1 1 2000
#3 3 2 1 1 2000
#4 3 3 1 1 2000
#5 1 1 2 2 2001
#6 2 1 2 2 2001
#7 3 2 2 2 2001
#8 3 3 2 2 2001
Or if the levels of 'occupation' and 'year' are only two, then we can also count with n_distinct to create a logical vector for filtering
df1 %>%
group_by(familyid, memberid) %>%
filter(n_distinct(occupation) >1 & n_distinct(year)> 1)
data
df1 <- structure(list(familyid = c(1L, 1L, 2L, 2L, 3L, 3L, 3L, 1L, 1L,
2L, 2L, 3L, 3L, 3L), memberid = c(1L, 2L, 1L, 2L, 1L, 2L, 3L,
1L, 2L, 1L, 2L, 1L, 2L, 3L), occupation = c(1L, 1L, 1L, 2L, 1L,
1L, 1L, 2L, 1L, 2L, 2L, 1L, 2L, 2L), panelid = c(1L, 1L, 1L,
1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 2L, 2L, 2L), year = c(2000L,
2000L, 2000L, 2000L, 2000L, 2000L, 2000L, 2001L, 2001L, 2001L,
2001L, 2001L, 2001L, 2001L)), class = "data.frame", row.names = c(NA,
-14L))