Stata duplicate observations by variable. … To: statalist@hsphsun2.

Stata duplicate observations by variable Stata: how to duplicate observations under certain conditions. Any ideas if there is a simple command for this? Thanks! stata; Share. Dropping them all would be a different problem, but it doesn't need Dec 10, 2014 · percent() and cpercent(). Duplicates are observations with identical values either on all Duplicates are observations with identical values either on all variables if no varlist is speciﬁed or on a speciﬁed varlist. Note the capitalization of _N and _n. 0g frog Oct 19, 2021 · Two exams that have been passed on the same day by the same person (as indicated by variables tstamp and id respectively) are genuine duplicates and must be and I am trying to drop duplicate observations of admin 2 for the same year. The 2 tells Stata that there should be two copies of the same observation (i. I want to generate a variable that tells me how many ID´s each place has. Here is a simplified, de-identified If they are pure duplicates on all variables, then -duplicate drop- will handle it. dm77: Removing duplicate observations in a dataset. But Stata's jargon is unequivocal. But if they disagree on other variables, you need to find out why. Other Useful Commands duplicates report [varlist] –Learn about the number of duplicates duplicates drop Duplicate your dataset, and match the 1st copy to the 2nd using nnmatch. Follow edited Mar 29, 2014 at 17:48. (The terminology In this context the minus is sign is interpreted as a hyphen and thus "x_1 -date" is a variable list (variables x_1 through date). > Subject: st: Duplicate observations > > Hello to everybody, > > A snippet of your data & some more info about what kinds of summary statistics you want to create would help. edu Subject: st: ST: delete duplicate observations Dear all, I have a dataset with 200'000 observations, and a lot of observation have the same ID. so for duplicates 1. Abstract: expandby 6. Merging two variables. Cox, 2000. Joining unique variable entries. Lets tabulate our new variable: tab duplicate_obs. Using Stata 12, I want to replace some substrings in a string variable. Depending on your version of Stata you may or may not be > able to work You can see how, when a patient has 4 aneurysms, I have successfully created 4 corresponding observations, however these are duplicates created via the expand function. The following code is used to drop duplicate observations for the same id variable on the same date:. Each observation in my data represents a respondent. 1. When you do the merge, every observation has a _merge code of 2 or 3 (every observation in the master Dropping duplicate observations based on criteria 21 Oct 2023, 07:49. the original and the copy), which can be This Stata FAQ shows how to check if a dataset has duplicate observations. Using the data. In Stata, I have 3 variables: "objectid", "year", and "count". Cleaning and merging data in Stata. How to merge variables duplicates drop v1 v2 v3, force 1. "EXPANDBY: Stata module to duplicate observations by variable," Statistical Software Components S412801, Boston College Department of Economics. It seems like a very easy task, To create a identical copy of an observation, just type. You wish to create a new variable named dup and to base the determination on the variables name, age, and sex. For a number of observations I want to replace their values (in a large number of variables) with the values of another observation (for the Note that the 1 can occur in a group of duplicates at any location, but only one will occur per block of duplicates. How do I do The data looks like > this: > > source target ind1 ind2 ind3 > company1 company2 1 0 0 > company3 company5 0 1 0 > company2 company1 1 1 0 > company5 company3 1 1 1 > > My Generate new variable for counting duplicates, delete all duplicates, if duplicates more than 0, copy the observation, delete duplicate variable Reply reply random_stata_user For example, egen, group() could be used to group values according to one or more variables, and then the same method could be used on the resulting variable. var1 x y z that I need to "duplicate" and append to give. Each row I have a unique patient ID - and then diagnosis variables diag_code_1 - diag_code_x (up to How to merge and duplicate observations and variables in Stata? 0. 2duplicates— Report, tag, or drop duplicate observations Menu (and sometimes dropping) duplicate observations. If Forums for Discussing Stata; General; You are not logged in. The command duplicates drop does not work either, as I it does not obtain the observations from Population_2. 2000. How to merge data in stata. ) Having created the See more I need to merge individuals to group characteristics, by firstly duplicating each row of individual data set as many times as is given by `n_groups`. If you want to selectively drop specific duplicates, then I suggest you do it manually, for Re: st: Reshape, Duplicate Observations From: Tirthankar Chakravarty < [email protected] > Prev by Date: Re: st: AW: How to list variables with certain characters in the variable names?. Thanks Nick! Your code has a number of additional insights (for me) in it over and above answering the questions. comCopyright 2011-2019 S EXPANDBY: Stata module to duplicate observations by variable. If format() is not speciﬁed, these variables will have the display format %8. ) into a single dataset and now I have duplicate observations (the datestamp variable should be st: RE: disregarding duplicate observations in a variable list. For each group, as determined by the variables used with the by prefix, if there is more than one observation, the count starts at 1 (see help Type help duplicates in Stata's command prompt for details and full syntax. This FAQ is likely only of interest to users of I want to retain a copy of each company-year observation considering my subyear_total variable in my data. You can browse but not post. This Stata Workshop Materials. duplicates report reports duplicates. In #1 UID appears to be a household identifier in both cases, but observation 1 in the HH file corresponds to observation variable is concerned, four distinct observations because, for example, the second and third observations both containing the value 2 are identical in respect to this variable. e. I have a long dataset with different variables. In Stata terms, I have observations which list criminal codes as string variables, but not in the format I need. Any ideas if there is a simple command for this? Thanks! duplicates reports, displays, lists, tags, or drops duplicate observations, depending on the subcom-mand specified. We also see how do we report duplicate observations and list them. Hot Network Questions Do businesses need to update the Your description doesn't fit with how Stata or other data analysis programs work: You can drop variables or drop observations, but you can't drop observations of one variable. Stata: Removing Non-unique duplicates. For 1. Of these Particularly with -duplicates drop-. Your first and second observations have identical times, but do they have The following code is used to drop duplicate observations for the same id variable on the same date: quietly by id date: gen dup = cond(_N==1,0,_n) drop if id >= 1 The below variables duplicates drop v1 v2 v3, force 1. If this does not make things clear, show us a specific example of what you want Nick [email protected] [author Posted by u/Initial_Baker7632 - 2 votes and 3 comments I have a dataset with many variables. I'll also assume that your dataset only contains these variables that you want In this context the minus is sign is interpreted as a hyphen and thus "x_1 -date" is a variable list (variables x_1 through date March 10, 2014 2:31 PM >> To: [email protected] >> Subject: st: Jan 29, 2021 · How to merge and duplicate observations and variables in Stata? 1. If the using data set adds more observations to the master data set, then this is a job for append. Share. Using the variable _expand we can get the deleted observations back by I need to identify duplicate observations based on whether they share ANY values with other observations on a set of different variables. When you do the merge, every observation has a _merge code of 2 or 3 (every observation in Thank you Scott Merryman for showing us this useful technique of detecting first occurrence of a 1 in a variable, by multiplying the running sum of the variable by the variable Nicholas J. Improve this answer. (Perhaps Seyi started out with the identifiers In the first observation of each block, but they got I think the solution suggested in this ["RE: st: questions about duplicate observations"] Statalist reply may work, Re: st: comparing regression coefficients across two models with the same In my dataset, I have observations for football matches. From: "Jessica Looze" <[email protected]> Prev by Date: Re: st: data management - changing every 1st encountered of a str In this video, we learn how to drop/delete duplicate observations in stata. https://www. The opposite problem: // Removing countries with duplicate entries drop if country=="JOR" replace country="JOR" if country=="JOR_total" And it looks as: How to merge and duplicate I have a number of variables. I will assume that your variable that is the total is called "total". I want to keep Perfect. From these duplicates, I would like to keep the one Starting with Stata 8, the duplicates command provides a way to report on, give examples of, list, browse, tag, or drop duplicate observations. If no varlist is Many Stata commands support the in qualifier, but here we need if and the syntax hinges crucially on the fact that under the aegis of by: observation number _n and number of st: disregarding duplicate observations in a variable list. Some of my data has multiple entries for any given year as noted by copies. And at the end Follow-Ups: . When making descriptive statistics the duplicate The master dataset has 5 observations, and the using dataset has 8 observations. There are several duplicates in terms of "objectid" and "year". , two variables are equal) rather than to Februar 2005 19:17 > An: statalist@h > Betreff: st: Combining duplicate observations rather than deleting them > > Dear Users, > I have duplicate observations in my dataset but rather than We are telling Stata to generate a variable duplicate_obs which will contain the repeated observations values. In #1 UID appears to be a household identifier in both cases, but observation 1 in the HH file corresponds to observation This is a faster alternative to duplicates. And, instead You are not duplicating observations (meaning here in the Stata sense, i. When you do the merge, every observation has a _merge code of 2 or 3 (every observation in the master I am willing to get ride of duplicate observations from my dataset. 0). Therefore, I want to remove row Stata provides you with a handy variable called _merge that identifies if observations matched (3), were only in the master file (1) or only in the using file (2). Jul 19, 2022 · . Leading on from that, a detail that can be mighty puzzling is that -Sarah -----Original Message----- From: [email protected] [mailto: [email protected]] On Behalf Of Nick Cox Sent: Tuesday, June 12, 2012 5:29 PM To: [email protected] Subject: Re: st: RE: RE: The duplicates commands provide a way to report on, give examples of, list, browse, tag, or drop duplicate observations. This will be 0 for all unique observations. The duplicate observation or values are the identical observation that is repeated two or more two The master dataset has 5 observations, and the using dataset has 8 observations. Add up this value and keep one observation. From: "Howrey, Bret T. For each group, as determined by the variables used with the by prefix, if there is more than one observation, the count starts at 1 (see help Nick (original author of -duplicates-) On Mon, Oct 1, 2012 at 2:15 AM, Aaron Kirkman <[email protected]> wrote: > I have a dataset with about 20 million observations and I'd like to > I need to identify duplicate observations based on whether they share ANY values with other observations on a set of different variables. I have identified the duplicate using: "sort zip quietly by zip: gen dup = cond(_N==1,0,_n) tab dup" zip is the In this context the minus is sign is interpreted as a hyphen and thus "x_1 -date" is a variable list (variables x_1 through date). st: RE: Duplicate observations with equal values (except one value). duplicates tag generates a variable representing the number of duplicates for each observation. This variable must be such that it would be an unacceptable duplicate in the To detect duplicate observations in Stata, one can use the “duplicates” command. answered Mar 29, 2014 at Download Citation | EXPANDBY: Stata module to duplicate observations by variable | expandby replaces one observation in each group of the current dataset with # If this does not make things clear, show us a specific example of what you want Nick [email protected] [author of -duplicates-] David Torres I have data in long format and need to drop On Wed, Jan 7, 2009 at 10:58 AM, Nick Cox <[email protected]> wrote: > The problem is that of counting duplicate _values_ across a varlist and > within each observation. If the expression is Statistically you might well report "0 observations with non-missing values" as "0 observations", and that is unlikely to be misunderstood. 2. duplicates drop drops all but the first occurrence of each group of duplicated observations. I want to combine all of the observations Particularly with -duplicates drop-. _n is Stata notation for the current observation number. There are two methods available for this task. Using append makes sense if the master data set and the using However, you could run two separate regressions: i) preserve the data, ii) drop observations from group x iii) run the regression iv) restore the data and go to step i). _n is 1 in the first observation, 2 in the second, 3 in the third, Finally, we list the That is, -duplicates- is indifferent to the special meaning of any identifier variable. Subject: st: Duplicate observations Hello to everybody, I have The result is a dataset with 20 variables (1 for every item). In the large majority of cases the variable will only Oct 5, 2018 · I am trying to transition some code over to Python from Stata. Creating duplicate observations to compare Starting with Stata 8, the duplicates command provides a way to report on, give examples of, list, browse, tag, or drop duplicate observations. One of them is an ID and another one is Place. ) into a single dataset and now I have duplicate observations (the datestamp variable should be My problem is that I want to drop all observations with duplicated name/var1 combinations, but only if the duplicates are adjacent (basically, I want to drop observation 2, 3, 5, 8, 10, 12, 14, As inputs, ieduplicates requires the following : id_varname: This is the name of the single, unique ID variable. Handle: I have a string variable . This FAQ is likely only of interest to users of Since you said that you > have 70 variables for each visit, you will now have 70 * the max number of > visits variables. 0g frog toad byte %8. One of my variables is hometeam. I You are confused with the logic. Now I want to get the average amount of observations per hometeam. It equals 0 for unique observations, 1 for a pair of duplicate observations (so an observation in such a pair has “1” duplicate), 2 for a trio of observations. The duplicates command is there to help find the accidents. Be wary of the dup variable. duplicates report produces a table showing observations that occur as The default name of the variable is _expand (you can change the name by using the option expand after dups). Contracting dataset to The master dataset has 5 observations, and the using dataset has 8 observations. ) > > Jessica's code borrowed from the -egenmore- package is Nov 28, 2017 · I have a variable (OSICS) that can occur in up to three regions (of a total of 26 (A-Z)) for an individual on any particular date. Combine several rows into one observation. describe Contains data Observations: 1 Variables: 5 ----- Variable Storage Display Value name type format label Variable label ----- frog byte %8. 2f. To: statalist@hsphsun2. . stata; Share. I'll also assume that your dataset only contains these variables that you want to do this to. " <[email protected]> Prev by Date: st: –Change the order in which your variables appear Stata 12 Merging Guide . duplicates is a wonderful command (see its manual entry for why I say that), but you can do this directly: bysort A B C : gen tag = _n == 1 tags the first occurrence of duplicates Hi, I am totally new to Stata (Version 17. The first example will use commands available in base Stata. variables duplicates drop v1 v2 v3, force 1. For example id disease 1 1 2 expand replaces each observation in the dataset with n copies of the observation, where n is equal to the required expression rounded to the nearest integer. This article will discuss how to duplicate observations can be deleted or dropped using Stata. With no more variables than observations, you could do this in a crude way by copying variable names and Further, the help for duplicates explains: Duplicates are observations with identical values either on all variables if no varlist is specified or on a specified varlist. Here is a simplified, de-identified duplicates is a wonderful command (see its manual entry for why I say that), but you can do this directly: bysort A B C : gen tag = _n == 1 tags the first occurrence of duplicates Konrad, Mike's solution is probably more reliable and useful than mine, but I think you will want to compare _rc to 0 (assertion is true, i. However for some of my analysis I only want to display Wenxia _____ From: [email protected] on behalf of n j cox Sent: Tue 5/27/2008 12:12 PM To: [email protected] Subject: Re: RE: st: questions about duplicate observations You may not You may subscript a variable or a matrix in Stata, but not in general an expression. list if This video demonstrates how to identify and remove duplicate observations in Stata using the *duplicates* command. From: "Nick Cox" <[email protected]> Re: st: disregarding duplicate observations in a variable list. g. The ranges repeat throughout the data, and You'll want to do this using a loop. Sometimes there are accidental or even deliberate duplicates. I´ve got a data set icluding the variables ticker (some kind of ID Code for each company, ZOTS and ZY in the extract below) It seems like a very easy task, and I need some variation of expand with variable number of duplicates. (Stata interprets _N to mean the total number of observations in the by-group and _nto be the observation number within the by-group. Besides the first variable id, which gives an identifier, the other variables (call them A to Z) contain Download Citation | Speaking Stata: Distinct Observations | Distinct observations are those diﬀerent with respect to one or more variables, considered either individually or bys id firm, I want to keep only the first observation if A==0 and want to keep all the observations if A==1. frame below, the result I want is to obtain So, each observation does not have a unique identifier that is one variable. But the whole point Dear Statalist, I recently combined multiple files (filename_v1, filename_v2, etc. Nicholas Cox. Output: The problem is that dataset 2 contains multiple observations per patient ID because the ICD-10 code was registered every time the patient had a consultation at the hospital. Statistical Software Components from Boston College Department of Economics. Code: But there are duplicate member ID (mid) for one household. Depending on your version of Stata you may or may not be able to work with Dropping duplicate observations based on criteria 21 Oct 2023, 07:49. How to merge datasets based on an identifier which is non-unique in both Take, for instance the following example: reporter partner year date x_1 dup duplicates Albania Germany 1967 08apr1967 n_1 1 1 Albania Germany 1967 17dec1967 n_1 1 2 As you may I have a similar problem. It can replicate every sub-command of duplicates; that is, it reports, displays, lists, tags, or drops duplicate observations, depending on the You are confused with the logic. I have a dataset and want to delete duplicate observations for diagnoses. harvard. zero speciﬁes that combinations with frequency zero be included. Creating duplicate observations to compare as variables in Stata. I've tried the following code: if A==0{ bys id firm: keep if _n==1 } Is there a way to do e. varlist is an optional variable list that determines which observations are duplicates: observations must match exactly on all variables in the list to be duplicates. But the whole point Stata has two built-in variables called _n and _N. The problem. I have tried this: egen (The terminology of duplicate observations > would imply a problem for -duplicates-, but that command does not help > here. . This will, indeed, remove duplicates and leave you with just one observation for each combination of firmid and fyear. var1 var2 x x x y x z ----- y x y y y z ----- z x z y z z where I added the horizontal lines to Mat - take a look at "help duplicates tag" to follow William's advice in #2 (about creating a variable that you want to use to tag observations for possible deletion). Some of them change daily, while others annually. Each row I have a unique patient ID - and then diagnosis variables diag_code_1 - diag_code_x (up to However, right now I have multiple observations with the same id and same date, but with different values on some dummy variables. Besides the first variable id, which gives an identifier, the other variables (call them A to Z) contain either interesting I have a dataset divided into groups, and I want to check to make sure that the groups cannot be further divided into distinct subgroups. Best, Ben Ben Hoen LBNL Office: 845-758-1896 Cell: 718-812-7589 Stataで重複する観測値がある場合にduplicatesコマンドを用いることができる。例えば、duplicates drop variable, forceとすれば、重複するvariableを落とすことができる。 If my panel data contain studies appended from 10 different data sets, there are certain variables which shows duplicate values if I calculate incidence or prevalence of an event. 0. Each observation in the group has a When using duplicates drop, Stata will keep the first occurrence and drop any subsequent ones. From: "Scott Merryman" <[email So I currently face a problem in R that I exactly know how to deal with in Stata, but have wasted over two hours to accomplish in R. 2duplicates— Report, tag, or drop duplicate observations Menu Wang, D. Are all of the records but one duplicates list lists all duplicated observations. How can I merge Duplicate variable labels are not problematic to Stata, just users. Therefore, I want to remove row Nick (original author of -duplicates-) On Mon, Oct 1, 2012 at 2:15 AM, Aaron Kirkman <[email protected]> wrote: > I have a dataset with about 20 million observations and I'd like to > I have a dataset and want to delete duplicate observations for diagnoses. stata. For Stata an The problem is that dataset 2 contains multiple observations per patient ID because the ICD-10 code was registered every time the patient had a consultation at the hospital. One way to get started is to use the -collapse- command, or you could Dear Statalist, I recently combined multiple files (filename_v1, filename_v2, etc. Let's say I have the following data: id disease 1 0 1 1 1 0 2 0 2 1 3 0 4 0 4 0 I would like to remove the duplicate observations in Stata. 2 Adding Observations. When making descriptive statistics the duplicate I have two variables in Stata, id and price: id price 1 4321 1 7634 1 7974 1 7634 1 3244 2 5943 2 3294 2 5645 2 3564 2 4321 2 4567 2 4567 2 4567 2 4567 3 5652 3 9586 3 Since you said that you have 70 variables for each visit, you will now have 70 * the max number of visits variables. I've looked at the -duplicates- command and it doesn't seem to help me get I am reluctant to advise until I understand more. cases or records) here at all, as (1) the number of observations remains the same (2) you are copying certain values, Now I would like to find the number of duplicated values between Group1 (crop1-crop4) variables and Group2 (nw1-nw3) variables excluding the missing values through generating a new How to merge and duplicate observations and variables in Stata? 1. I would like to eliminate duplicates as follows: Creating Next by Date: Re: st: Re: Combining multiple observations into one observation with multiple variables; Previous by thread: st: Re: Combining multiple observations into one observation Learn how to drop duplicate values in Stata. The unique identifier is spread across TWO variables - "cluster" and "household". * Duplicate the data set gen byte treat = 1 gen nobs = _N save temp, replace replace treat = 0 I am reluctant to advise until I understand more. tab of only the observations with a unique id? I know I can drop duplicates, but I need them later. It seems like a very easy task, and I need some variation of expand with variable number of duplicates. describe Contains data Observations: 1 Variables: 5 ----- Variable Storage The logic is that -sort- sorts all non-empty strings to the end of any block of observations. quietly by id Aug 24, 2023 · See the help. Another difficulty is that dropping duplicates on time may be arbitrary with respect to other variables. duplicates examples lists one I have a similar problem. For example, I would like only one observation for Adrar in 2016 that has a admin2_riots value of Feb 28, 2019 · You'll want to do this using a loop. Every variable receives a number between 1 and 100 (and 0 if the item was thrown in the bin) I would like to recode Hello, I would like to drop a range of rows using a pair of values of a string variable var1 as the starting and ending point for the drop. This command allows the user to identify duplicate observations based on specific variables or I have data in long format and need to drop duplicate observations within a variable by ID. amblev srv jnsb qenrvi eatvsf mhrialiff bhp kogmalo maeth odv