select maximum row value by group - r

I've been trying to do this with my data by looking at other posts, but I keep getting an error. My data new looks like this:
id year name gdp
1 1980 Jamie 45
1 1981 Jamie 60
1 1982 Jamie 70
2 1990 Kate 40
2 1991 Kate 25
2 1992 Kate 67
3 1994 Joe 35
3 1995 Joe 78
3 1996 Joe 90
I want to select the row with the highest year value by id. So the wanted output is:
id year name gdp
1 1982 Jamie 70
2 1992 Kate 67
3 1996 Joe 90
From Selecting Rows which contain daily max value in R I tried the following but did not work
ddply(new,~id,function(x){x[which.max(new$year),]})
I've also tried
tapply(new$year, new$id, max)
But this didn't give me the wanted output.
Any suggestions would really help!

Another option that scales well for large tables is using data.table.
DT <- read.table(text = "id year name gdp
1 1980 Jamie 45
1 1981 Jamie 60
1 1982 Jamie 70
2 1990 Kate 40
2 1991 Kate 25
2 1992 Kate 67
3 1994 Joe 35
3 1995 Joe 78
3 1996 Joe 90",
header = TRUE)
require("data.table")
DT <- as.data.table(DT)
setkey(DT,id,year)
res = DT[,j=list(year=year[which.max(gdp)]),by=id]
res
setkey(res,id,year)
DT[res]
# id year name gdp
# 1: 1 1982 Jamie 70
# 2: 2 1992 Kate 67
# 3: 3 1996 Joe 90

Just use split:
df <- do.call(rbind, lapply(split(df, df$id),
function(subdf) subdf[which.max(subdf$year)[1], ]))
For example,
df <- data.frame(id = rep(1:10, each = 3), year = round(runif(30,0,10)) + 1980, gdp = round(runif(30, 40, 70)))
print(head(df))
# id year gdp
# 1 1 1990 49
# 2 1 1981 47
# 3 1 1987 69
# 4 2 1985 57
# 5 2 1989 41
# 6 2 1988 54
df <- do.call(rbind, lapply(split(df, df$id), function(subdf) subdf[which.max(subdf$year)[1], ]))
print(head(df))
# id year gdp
# 1 1 1990 49
# 2 2 1989 41
# 3 3 1989 55
# 4 4 1988 62
# 5 5 1989 48
# 6 6 1990 41

You can do this with duplicated
# your data
df <- read.table(text="id year name gdp
1 1980 Jamie 45
1 1981 Jamie 60
1 1982 Jamie 70
2 1990 Kate 40
2 1991 Kate 25
2 1992 Kate 67
3 1994 Joe 35
3 1995 Joe 78
3 1996 Joe 90" , header=TRUE)
# Sort by id and year (latest year is last for each id)
df <- df[order(df$id , df$year), ]
# Select the last row by id
df <- df[!duplicated(df$id, fromLast=TRUE), ]

ave works here yet again, and will account for a circumstance with multiple rows for the maximum year.
new[with(new, year == ave(year,id,FUN=max) ),]
# id year name gdp
#3 1 1982 Jamie 70
#6 2 1992 Kate 67
#9 3 1996 Joe 90

Your ddply effort looks good to me, but you referenced the original dataset in the callback function.
ddply(new,~id,function(x){x[which.max(new$year),]})
# should be
ddply(new,.(id),function(x){x[which.max(x$year),]})

Related

Fill values in between values in rows in R based on condition

I have data that look like this:
id <- c(rep(1,5), rep(2,5), rep(3,4), rep(4,2), rep(5, 1))
year <- c(1990,1991,1992,1993,1994,1990,1991,1992,1993,1994,1990,1991,1992,1994,1990,1994, 1994)
gender <- c(rep("female", 5), rep("male", 5), rep("male", 4), rep("female", 2), rep("male", 1))
dat <- data.frame(id,year,gender)
As you can see, id 1 and 2 have observations for every year between 1990 and 1994, while there are missing observations in between 1990 and 1994 for ids 3 and 4, and, finally, only one observation for id 5.
What I want to do is to copy column id and gender and insert the missing observations for id 3 and 4 so that there are observations from 1990 too 1994, while I want to do nothing with id 1, 2 or 5. Is there are way to create a sequence with numbers from the oldest to the newest observation based on the condition that there is a gap between two numbers grouped by a variable, such as id?
The final result should look like this:
id year gender
<dbl> <dbl> <chr>
1 1 1990 female
2 1 1991 female
3 1 1992 female
4 1 1993 female
5 1 1994 female
6 2 1990 male
7 2 1991 male
8 2 1992 male
9 2 1993 male
10 2 1994 male
11 3 1990 male
12 3 1991 male
13 3 1992 male
14 3 1993 male
15 3 1994 male
16 4 1990 female
17 4 1991 female
18 4 1992 female
19 4 1993 female
20 4 1994 female
21 5 1994 male
Filter the dataset for id 3 and 4, complete their observations and bind the data to other id's where id is not 3 and 4.
library(dplyr)
library(tidyr)
complete_id <- c(3, 4)
dat %>%
filter(id %in% complete_id) %>%
complete(id, year = 1990:1994) %>%
fill(gender) %>%
bind_rows(dat %>% filter(!id %in% complete_id)) %>%
arrange(id)
# id year gender
#1 1 1990 female
#2 1 1991 female
#3 1 1992 female
#4 1 1993 female
#5 1 1994 female
#6 2 1990 male
#7 2 1991 male
#8 2 1992 male
#9 2 1993 male
#10 2 1994 male
#11 3 1990 male
#12 3 1991 male
#13 3 1992 male
#14 3 1993 male
#15 3 1994 male
#16 4 1990 female
#17 4 1991 female
#18 4 1992 female
#19 4 1993 female
#20 4 1994 female
#21 5 1994 male

Average of a variable by collapsing two columns in r [duplicate]

This question already has answers here:
Aggregate / summarize multiple variables per group (e.g. sum, mean)
(10 answers)
Closed 4 years ago.
I would wish to find the average per season for each year. Each year is observed 4 times. The seasons are two but are repeated twice as shown below
year=rep(c(1990:1992),each=4)
season=c("W","D","W","D","W","W","D","D","D","W","W","D")
temp=c(28,25,26,21,28,25,20,20,20,35,28,21)
df=data.frame(year,season,temp)
which gives
year season temp
1 1990 W 28
2 1990 D 25
3 1990 W 26
4 1990 D 21
5 1991 W 28
6 1991 W 25
7 1991 D 20
8 1991 D 20
9 1992 D 20
10 1992 W 35
11 1992 W 28
12 1992 D 21
i want to collapse this data to have the average of the two seasons for each year as below
year season avgtemp
1 1990 D 23.0
2 1990 W 27.0
3 1991 D 20.0
4 1991 W 25.1
5 1992 D 20.5
6 1992 W 31.5
How can i obtain this?
Try below:
aggregate(df[, 3], df[, 1:2], mean)
library(tidyvere)
df %>%
group_by(year,season) %>%
summarise(avgtemp=mean(temp))
# A tibble: 6 x 3
# Groups: year [?]
year season avgtemp
<int> <fct> <dbl>
1 1990 D 23
2 1990 W 27
3 1991 D 20
4 1991 W 26.5
5 1992 D 20.5
6 1992 W 31.5

unlist and merge into a single dataframe in r

I have a list of dataframes that I need to be combined into a single one.
year<-1990:2000
v1<-1:11
v2<-20:30
df1<-data.frame(year,v1)
df2<-data.frame(year,v2)
ldf<-list(df1,df2)
I now want to unlist this dataframe and get
> head(df)
year v1 v2
1 1990 1 20
2 1991 2 21
3 1992 3 22
4 1993 4 23
Note that my question is different from the solution provided in a similar question, where the solution to that question was: `df <- ldply(ldf, data.frame)
Because what I am essentially looking for, is a more automatic way of doing this: df<-merge(df1,df2, by="year")
With more number of list elements, a convenient option is reduce with one of the join functions
library(tidyverse)
ldf %>%
reduce(inner_join, by = "year")
# year v1 v2
#1 1990 1 20
#2 1991 2 21
#3 1992 3 22
#4 1993 4 23
#5 1994 5 24
#6 1995 6 25
#7 1996 7 26
#8 1997 8 27
#9 1998 9 28
#10 1999 10 29
#11 2000 11 30
Is there anything wrong with:
df <- merge(ldf[[1]], ldf[[2]], by="year")
Or for a long list:
df1 <- ldf[[1]]
for (x in 2:length(ldf)) {
df1 <- merge(df1, ldf[[x]])
}
# year v1 v2
# 1 1990 1 20
# 2 1991 2 21
# 3 1992 3 22
# 4 1993 4 23
# 5 1994 5 24
# 6 1995 6 25
# 7 1996 7 26
# 8 1997 8 27
# 9 1998 9 28
# 10 1999 10 29
# 11 2000 11 30

How to remove subjects with missing yearly observations in R?

num Name year age X
1 1 A 2011 68 116292
2 1 A 2012 69 46132
3 1 A 2013 70 7042
4 1 A 2014 71 -100425
5 1 A 2015 72 6493
6 2 B 2011 20 -8484
7 3 C 2015 23 -120836
8 4 D 2011 3 -26523
9 4 D 2012 4 9923
10 4 D 2013 5 82432
I have the data which is represented by various subjects in 5 years. I need to remove all the subjects, which are missing any of years from 2011 to 2015. How can I accomplish it, so in given data only subject A is left?
Using data.table:
A data.table solution might look something like this:
library(data.table)
dt <- as.data.table(df)
dt[, keep := identical(unique(year), 2011:2015), by = Name ][keep == T, ][,keep := NULL]
# num Name year age X
#1: 1 A 2011 68 116292
#2: 1 A 2012 69 46132
#3: 1 A 2013 70 7042
#4: 1 A 2014 71 -100425
#5: 1 A 2015 72 6493
This is more strict in that it requires that the unique years be exactly equal to 2011:2015. If there is a 2016, for example that person would be excluded.
A less restrictive solution would be to check that 2011:2015 is in your unique years. This should work:
dt[, keep := all(2011:2015 %in% unique(year)), by = Name ][keep == T, ][,keep := NULL]
Thus, if for example, A had a 2016 year and a 2010 year it would still keep all of A. But if anyone is missing a year in 2011:2015 this would exclude them.
Using base R & aggregate:
Same option, but using aggregate from base R:
agg <- aggregate(df$year, by = list(df$Name), FUN = function(x) all(2011:2015 %in% unique(x)))
df[df$Name %in% agg[agg$x == T, 1] ,]
Here is a slightly more straightforward tidyverse solution.
First, expand the dataframe to include all combinations of Name + year:
df %>% complete(Name, year)
# A tibble: 20 x 5
Name year num age X
<fctr> <int> <int> <int> <int>
1 A 2011 1 68 116292
2 A 2012 1 69 46132
3 A 2013 1 70 7042
4 A 2014 1 71 -100425
5 A 2015 1 72 6493
6 B 2011 2 20 -8484
7 B 2012 NA NA NA
8 B 2013 NA NA NA
9 B 2014 NA NA NA
10 B 2015 NA NA NA
...
Then extend the pipe to group by "Name", and filter to keep only those with 0 NA values:
df %>% complete(Name, year) %>%
group_by(Name) %>%
filter(sum(is.na(age)) == 0)
# A tibble: 5 x 5
# Groups: Name [1]
Name year num age X
<fctr> <int> <int> <int> <int>
1 A 2011 1 68 116292
2 A 2012 1 69 46132
3 A 2013 1 70 7042
4 A 2014 1 71 -100425
5 A 2015 1 72 6493
Just check which names have the right number of entries.
## Reproduce your data
df = read.table(text=" num Name year age X
1 1 A 2011 68 116292
2 1 A 2012 69 46132
3 1 A 2013 70 7042
4 1 A 2014 71 -100425
5 1 A 2015 72 6493
6 2 B 2011 20 -8484
7 3 C 2015 23 -120836
8 4 D 2011 3 -26523
9 4 D 2012 4 9923
10 4 D 2013 5 82432",
header=TRUE)
Tab = table(df$Name)
Keepers = names(Tab)[which(Tab == 5)]
df[df$Name %in% Keepers,]
num Name year age X
1 1 A 2011 68 116292
2 1 A 2012 69 46132
3 1 A 2013 70 7042
4 1 A 2014 71 -100425
5 1 A 2015 72 6493
Here is a somewhat different approach using tidyverse packages:
library(tidyverse)
df <- read.table(text = " num Name year age X
1 1 A 2011 68 116292
2 1 A 2012 69 46132
3 1 A 2013 70 7042
4 1 A 2014 71 -100425
5 1 A 2015 72 6493
6 2 B 2011 20 -8484
7 3 C 2015 23 -120836
8 4 D 2011 3 -26523
9 4 D 2012 4 9923
10 4 D 2013 5 82432")
df2 <- spread(data = df, key = Name, value = year)
x <- colSums(df2[, 4:7], na.rm = TRUE) > 10000
df3 <- select(df2, num, age, X, c(4:7)[x])
df4 <- na.omit(df3)
All steps can of course be constructed as one single pipe with the %>% operator.

filter a df with NA to get only individuals that appear more than one time in r

I am using a national survey to run a regression: the survey is conducted every two years and some individual are repeatedly interviewed while others just one time.
Now I want to make the df a panel one (have only the individual that appears more than one time). The df is like this:
year nquest nord nordp sex age
2000 10 1 1 F 40
2000 10 2 2 M 43
2000 30 1 1 M 30
2002 10 1 1 F 42
2002 10 2 2 M 45
2002 10 3 NA F 15
2002 30 1 1 M 32
2004 10 1 1 F 44
2004 10 2 2 M 47
2004 10 3 3 F 17
2004 50 1 NA M 66
where nquest is the code number of the family, nord is the code number of the individual and nordp is the code number that the individual had in the previous survey; when a new individual is interviewed the value in nordp is "missing" (R automatically insert NA). For example the individual 3 of family 10 has nordp=NA in 2002 because it is the first time that she is interviewed, while in 2004 nordp is 3 (because 3 was the number that she had in 2002).
I can't use nord to filter the df because the composition of the family may change (for example in 2002 in family x the mother has nordp=2 (it means that in 2000 nord was 2) and nord=2 but the next year nord could be 1 (for example if she gets divorced) but nordp is still 2).
I tried to filter using this command:
df <- df %>%
group_by(nquest, nordp)
filter(n()>1)
but I don't get the right df because if for the same family there are more than one individual insert (NA) they will be considered as the same person since nordp is NA the first time.
How can I consider also the individual that appears for the first time in a certain year (nordp=NA)? I tried to a create a command using age (the age in t shoul be equal to (age (in t-2) + 2; for example in 2000 age is 20, in 2002 is 22) but it didn't worked.
Consider that the df is composed by thousand observations and I can't check manually.
The final df should be:
year nquest nordp sex age
2000 10 1 F 40
2000 10 2 M 43
2000 30 1 M 30
2002 10 1 F 42
2002 10 2 M 45
2002 10 3 F 15
2002 30 1 M 32
2004 10 1 F 44
2004 10 2 M 47
2004 10 3 F 17
As you can see there are only the individual that appears more than one time and nquest=10 nordp=30 appears three times; with my command it appears just two times because in the first year nordp was NA.
We wish to assign unique IDs to individuals, then filter by the count of unique IDs. The main idea is to chain together the nordp and nord values within each family over years. Here's an idea inspired by Identify groups of linked episodes which chain together. First, load the igraph package, via library(igraph). Then the following function assigns IDs for a given family.
assignID <- function(d) {
fields <- names(d) # store original column names
d$nordp[is.na(d$nordp)] <- seq_len(sum(is.na(d$nordp))) + 100
d$nordp_x <- (d$year-2) * 1000 + d$nordp
d$nord_x <- d$year * 1000 + d$nord
dd <- d[, c("nordp_x", "nord_x")]
gr.test <- graph.data.frame(dd)
links <- data.frame(org_id = unique(unlist(dd)),
id = clusters(gr.test)$membership)
d <- merge(d, links, by.x = "nord_x", by.y = "org_id", all.x = TRUE)
d$uid <- d$nquest * 100 + d$id
d[, c(fields, "uid")]
}
The function can "tell", for example, that
year nordp nord
2000 1 1
2002 1 2
2004 2 3
is the same individual, by chaining together the nordp and nord over the years, and assigns the same unique ID to all 3 rows. So, for example,
assignID(subset(df, nquest == 10))
# year nquest nord nordp sex age dob uid
# 1 2000 10 1 1 F 40 1960 1001
# 2 2000 10 2 2 M 43 1957 1002
# 3 2002 10 1 1 F 42 1960 1001
# 4 2002 10 2 2 M 45 1957 1002
# 5 2002 10 3 101 F 15 1987 1003
# 6 2004 10 1 1 F 44 1960 1001
# 7 2004 10 2 2 M 47 1957 1002
# 8 2004 10 3 3 F 17 1987 1003
gives us an additional column with the uid for each individual.
The remaining steps are straightforward. We split the dataframe by nquest, apply assignID to each subset, and rbind the output:
dd <- do.call(rbind, by(df, df$nquest, assignID))
Then we can just group by uid and filter by count:
dd %>% group_by(uid) %>% filter(n()>1)
# Source: local data frame [10 x 8]
# Groups: uid [4]
# year nquest nord nordp sex age dob uid
# <int> <int> <int> <dbl> <fctr> <int> <int> <dbl>
# 1 2000 10 1 1 F 40 1960 1001
# 2 2000 10 2 2 M 43 1957 1002
# 3 2002 10 1 1 F 42 1960 1001
# 4 2002 10 2 2 M 45 1957 1002
# 5 2002 10 3 101 F 15 1987 1003
# 6 2004 10 1 1 F 44 1960 1001
# 7 2004 10 2 2 M 47 1957 1002
# 8 2004 10 3 3 F 17 1987 1003
# 9 2000 30 1 1 M 30 1970 3001
# 10 2002 30 1 1 M 32 1970 3001

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