Count observations in stata. See [no]means option above.

Count observations in stata One of the confidentiality rules that I have to follow is that I can't publish results that allow identification of any individual from the data. It is a built-in system variable that contains the number of the current observation. The in qualifier uses a numlist to give a range of observations that should be listed. Here are the definitions for count and sum with weights: count: unweighted: N i, the number of observations in group i aweight: N i, the number of observations in group i fweight, iweight, pweight: P w j, the sum of the weights over This first step maps the distinct values of varname to 1, 2, 3, and up to the number of distinct values. Someone rushed down to marketing and came back with two new Stata polo shirts for him to change. You can also state the first two numbers of your pattern and use a colon : or write “to” the number you want to end the sequence on. Re: st: Counting observations within groups. Jan 20, 2021 · I can't follow this, but the number of observations in each panel is. id 2 has two observations within the next year after February 1st, 2000. missing()—Countmissingandnonmissingvalues Description Syntax Remarksandexamples Conformability Diagnostics Alsosee Description The rule is to calculate the number of any occurrences in the matched id (disregarding whether it is treated or not) within one year starting from the date of the treated observations. I found the command finally. And also, once I would manage that I would like to be able to change the distance of the scale distance (in the third graph the count is much more frequent (absolute number of patients) than on the one I managed to create). It is equally the observation number of the last observation in each such group. e. In section 2, I point out some elements we should always account for when counting observations for survey data. Variable that double counts the observations. There are different methods of doing this i. Negative numbers count from the end of the dataset. , job_code). Please see the output below: Below, for reference, are the st: Count observations per year. For each person in each family, it may be useful to calculate variables that summarize properties of the other members of the same family. And if you type gene seqord=_n-1 then Stata will generate a variable named -seqord-, whose value is the sequential order of the observation in the In this example, observation number 2 was selected twice, and observations 8 and 3 were each selected once. From: "raoul reulen" <[email protected]> Prev by Date: st: output of xtdpd; Next by Date: st: Counting interactions within a group; Previous by thread: Re: st: Estout and number of observations I also tried "svy: tabulate nativity, obs", but that gives us the unweighted number of observations. Finally, the result of the sum is assigned to the fixed observation using the variable counter. Nov 16, 2022 · This command puts the observations in the order of oldid. list mpg if rep78 you will get a list for all observations, because rep78 is never 0. Stata collapse ( mean ) lexp_mean=lexp gnppc_mean=gnppc (sd) lexp_sd=lexp gnppc_sd=gnppc ( count ) lexp_count=lexp gnppc_count=gnppc, by ( region ) Jan 16, 2021 · I want to calculate the total number of times region and urban have changed during the observation period for each individual. Definition of "count" command in Stata is "Count observations s Sep 30, 2020 · Svend Juul's great teaching materials (Introduction to Stata 7 and Introduction to Stata 8) are introductory textbooks in my beginning of Stata use. , collapse, contract, statsby)that We use count command to count the number of observations that meet a specific condition. These make the use of Stata be prone to err. Since my dataset has over 6000 observations, what commands should I use to generate a count of unique ids? egen—Extensionstogenerate Description Quickstart Menu Syntax Remarksandexamples Acknowledgments References Alsosee Description For the variable nomiss, observations 1, 5 and 6 had three valid values, observations 2 and 3 had two valid values, observation 4 had only one valid value and observation 7 had no valid values. Perfect. From: "Weichle, Thomas" <[email protected]> Prev by Date: Re: st: Creating a variable; Next by Date: st: Re: increasing time burden during resampling; Previous by thread: Re: st: Command to identify number of unique individuals; Next by thread: st: exiting Stata from within Stata; Index(es duplicates—Report,tag,ordropduplicateobservations Description Quickstart Menu Syntax Options Remarksandexamples Storedresults Acknowledgments References Alsosee exp specifies the size of the sample, which must be less than or equal to the number of sampling units in the data. su group, meanonly Among other things, this second step leaves behind in r(max) the number of distinct values; see [R] summarize for details on saved results. parentheses ( ) between the number you want to start at and the number you want to end at. The variable miss shows the opposite; it provides a count of the number of missing values. I have a dataset, and I wish to work with a subset of observations, and that subset is defined by a complicated criterion. Variable number is the numbering within each group. cox@durham. I know that using egen countnum=count( id ), by( id ) is a correct way to know whether the id is repeated, but what I do not know is whether this is a correct way to count whether the id repeat in the same place through time. g. dta. Drops the variables used only for this process. First thing I tried was lagged values: bysort i: gen urban_lag = l1. We will create a dummy variable that is 1 if the kid is a boy (0 if not), and a dummy variable that is 1 if the kid is a girl (and 0 if not). Now, I want to count the number of observations that occur one year starting from the date of each treatment observation (excluding itself) within this group. It was basically a function di c(k) that returns the row numbers. If the data are weighted, the frequency refers to the sum of the weights. ) In our example, we have one group of observations with duplicates consisting of observation number 1, 7 and 8. You know that everybody in your company makes a salary between $6,000 and Nov 16, 2022 · where V_srs is an estimate of the variance of the mean assuming a simple random sample (of the same size as your survey dataset) and n is the number of observations. Although we chose to tag the first observation in each group, as was specified by _n == 1, we could have done it also for the last observation in each group, for which the code is _n == _N. com Current data management and analysis may hinge on detecting (and sometimes dropping) duplicate observations. This is different from the count of non-missing observations up until a certain Aug 23, 2018 · I don't care about the value of the observations, just whether or not they answered the question item (non-missing). sample—Drawrandomsample Description Quickstart Menu Syntax Options Remarksandexamples References Alsosee Description sampledrawsrandomsamplesofthedatainmemory Is there a way to display the total number of observations corresponding to each of the histograms obtained with the command? I searched in the Graphics Stata 1. The observations are uniquely identified by ids for persons and their neighbors and by year. This portfolio contains 32 observations. _n is the Stata way of referring to the observation number; in a 10-observation dataset, _n takes Here is a similar example sysuse auto collapse (count) count=mpg (mean) mpg weight , by(rep78) It follows from the help that you need to give different variable names for the second and later statistics based on any variable (-mpg- above). In other words, as my panel is not balanced, I need to define the time window for a rolling 36-month regression (the rolling command is way too slow, as my dataset contains 1m+ observations). Thank you sir for hinting to a more compact way of doing it. You could implement Andrew's solution fairly generally with the following code. 经管之家(原经济论坛)-国内活跃的经济、管理、金融、统计在线教育和咨询网站 percentage terms. Thus [1] denotes the first observation, and [_N] denotes the last observation within each group. Here are some examples: . Bob said it was 522, so you check it. _N denotes the total number of rows. Here we can rely on Stata to generate or replace observations in the current sort order (and, moreover, for any use of time-series operators to work, the data must be in tsset order). The following example loads up an automotive dataset included with Stata and counts the number of foreign and domestic cars in it. 在Stata中进行数据分析和处理时，我们经常需要统计某个变量的个数，比如，计算某个分类变量的不同取值的个数，或者某个数值变量中满足特定条件的记录数。以下是详细的步骤，教您如何在Stata中计算个数。 1. stata command: count if sex==1 & group1==2 count if sex==1 & group2=="A" count counts the number of observations that satisfy the specified conditions. only the sum, count, sd, semean, and sebinomial statistics. From: Nahla Betelmal <[email protected]> Jan 28, 2013 · Stata - Count observations within window. For example, you Stata likes to think of a histogram as an empirical approximation to a probabilithy distribution function, but to get the kind of histogram you learned about in elementary school where the height of the bar is proportional to the number of observation in the bin, add the freq option: st: Command to identify number of unique individuals. To base the duplicate count solely on name, type Oct 3, 2016 · What I need to find out is: per fund id : how many observations are there between the actual monthnum[_n] and monthnum[_n]-36. uk Abstract. edu count—Countobservationssatisfyingspecifiedconditions Description Quickstart Menu Syntax Remarksandexamples Storedresults References Alsosee Description Jan 28, 2021 · I would like to create a variable ("new_var") that counts the number of distinct values of "var_of_interest" that are different from "BA". Let j index observations and i index by-groups. Counting panels, and more generally groups, is sometimes possible in Stata through a reduction command (e. Remember, N reflects the total number of observations in the dataset; see [U] 13. If the argument were just a number, then the same logic still applies. This number increases from 1 at observation 1 (cd1 first occurs), to 2 at observation 2 (cd2 first occurs), to 3 at observation 4 (cd3 first occurs), and so forth. Entries can take values 0, 1, or 2 (I use Stata/SE 11). I am working with micro-level data provided by my local government. What I am looking for is to create a variable (or collapse data) that shows how many jobs they have throughout the year from 1994 to 1996. Nov 29, 2021 · I have one question related to counting distinct values by groups. * is used to duplicate a string 0 or more times. Explore techniques. 4 System variables Jul 4, 2023 · We discuss the methods to get unique number of observations in Stata. These functions return the indicated count of missing or nonmissing values. Jan 9, 2019 · Hello friends,What's up! In this video, I am coming with a new Stata Command which is "count". From: "Dascha Orlova" <[email protected]> Re: st: Count observations per year. 59 419156. From: Nick Cox <[email protected]> References: st: Counting observations between dates by group. 3 744023. Sep 5, 2020 · Stata has variables and observations, which have important differences from arbitrary rows and columns in Excel. From: Daniel Escher <[email protected]> Prev by Date: Re: st: Loading long string variables (from SQL) into Stata; Next by Date: st: Reshaping long to wide data from complex experimental design; Previous by thread: Re: st: Counting observations within groups Nov 16, 2022 · If varname were equal to any other value, Stata would deny the assertion. Variables are ordered from those with the most missing values to those with the least. Answer: it's not, so the company took egen, sum() undocumented in Stata 9 and documented a total() function instead, But they didn't want to break any existing code and so sum Nov 16, 2022 · The variable nvals now contains the number of distinct observations. For some cases, this number may be different from the number reported in the output for the analogous survey estimation on the whole population. In the table, each column sums to the total number of observations in the data, 125. Suppose you wanted a count of the number of boys and girls in the family. The first block of columns in the output shows the patterns of missing data. Please kindly give me any answers or comments to me! Sep 23, 2020 · But the company have, surprise, Stata solutions for Stata problems. Jun 15, 2019 · The thing is I have an append with lots of observations and these observations can be the same id in a different year. Afterwards, I use summarize to add-up the number of such observations. Example 4 Jun 25, 2019 · The data set is a network panel, in which some variables refer to 'neighbors' of persons in a given year. Thanks Nick! Your code has a number of additional insights (for me) in it over and above answering the questions. " ) in the list } Experienced Stata users have often seen this advice: Do not loop over observations, as it is usually not the best way to do something. by oldid: gen newid = 1 if _n == 1 This command creates a new variable newid that is 1 for the first observation for each individual and missing otherwise. (For more information on this, see FAQ: What is true and false in Stata? . I guess there might be a command to give me number of variables (columns). Other than being bound by quotation marks, words in Stata are just defined by being separated by spaces. Nov 16, 2022 · Different sequences of consecutive numbers can be generated by using an expression that includes _n for x and by setting y equal to the total number of observations within each repeated pattern. From: "Impavido, Gregorio" <[email protected]> Re: st: RE: perform regression on minimum number of observations stata. How to count in R? Thank you. Jan 19, 2018 · count() will accept string variables. st: perform regression on minimum number of observations stata. Now we will use the command dups. codebook, contract, unique, distinct, le For instance: id year x1 111 1999 3 111 2000 5 111 2001 6 123 2000 4 123 2001 2 For the above example, there are 2 unique ids (111 and 123). where "new_var" is the variable that retrieves the quantity of interest for each different id (from the variable "var_id"). Counting values to get a matrix in Stata. urban bysort i (year): gen urbanchange = 0 if urban==urban_lag & !missing(urban) replace urbanchange = 1 if urban!=urban_lag & !missing(urban). See full list on stats. The second table contains the information on the pattern of missing values. Bob’s second claim was that the data are for only full-time employees. ") in the list } Experienced Stata users have often seen the advice: Don't loop over observations, as it is usually not the best way to do something. Aug 7, 2017 · All the code does is count words inside a string. For example, ID 1 had 3 jobs, ID 2 had 1 and ID 3 had 3. From: Nahla Betelmal <[email protected]> st: RE: perform regression on minimum number of observations stata. Oct 14, 2024 · Stata如何计算个数：详解操作步骤. If no conditions are specified, count displays the number of observations in the data. Examples: data on families. How to count the number of observations in R like Stata command count. Cox Department of Geography Durham University Durham City, UK n. by id : egen A_nm = count(A) May 29, 2019 · Counting unique values in Stata May 29, 2019 In order to get the unique values of a variable (for example how many times an identifier occurs among observations) there are a few different approaches we can try. I have data that shows the age at each event over a lifetime (age_at_event1-age_at_event3), as well as the age at which I am no longer interested in counting such events (stop_age). This logic also can be useful with if. Ideal output would be a single number (i. The last line generates a new variable with the number of observations per industry and year that have no missing values Aug 16, 2015 · I had the same problem to count the occurrences of specific values in each observation across a set of variables. list make price mpg weight gear_r ~o foreign 1. com count may strike you as an almost useless May 14, 2020 · egen, rowmiss() returns the number of missing values for the variables in (), rowwise. Number of unique values of mpg is 21. Jul 11, 2024 · Stata has two system variables that always exist as long as data is loaded, _n and _N. Please do read and act on FAQ Advice #12. The seed is the number with which Stata (or any other By contrast, the npresent command shows us the number of non-missing values for all of the variables in our data file. Creates a fifth new variable, the unemployment rate I actually want, by calculation from the raw numbers. 7 Stored results total stores the following in e(): Scalars e(N) number of observations e(N over) number of subpopulations e(N clust) number of If you type gene seqnum=_n then Stata will generate a variable named -seqnum-, whose value is the sequential order of the observation in the dataset, starting from 1 for the first observation. bysort id : gen count = _N and the number of non-missing values of A is. My apologies. 使用count命令 Mar 28, 2014 · Every observation is compared with the one observation that is fixed by the loop. From this, we see all of the variables have 200 non-missing observations, except for science that has 195 non-missing observations. Dec 17, 2013 · The system variable _n is fixed in the sense that it denotes the number of the current observation independently of your if condition. Row-wise count/sum of values in Stata. Nov 17, 2014 · sum(): doesn't do the job, the graphical output displays the number of observations, but Stata's poor language concept doesn't allow programmatic retrieval of the value, nor does it provide any points of entry for information retrieval in the manual via help. count counts the number of observations that satisfy the specified conditions. What you are asking for with your code is a counter that takes on the value of the number of the observation if it is not missing. Am I wrong? I am aware of other ways to compute the number of unique values in Stata, but it would be so convenient to add this feature to the codebook command. Nov 16, 2022 · (Stata interprets _N to mean the total number of observations in the by-group and _n to be the observation number within the by-group. colnonmissing(X) returns the count of nonmissing values of each column of X, rownonmiss- Nov 11, 2014 · I am trying to count the number of times an event occurred before a particular age. If the data are not weighted, the number of observations is identical to the frequency, and by default only the frequency is reported. Nov 16, 2022 · Question. We can do that with one extra step. "33" if 33 groups of a total 35 met the condition). You say place and Place in different places, but you don't give us a data example to make clear what is going on. From: "Austin Nichols" <[email protected]> Prev by Date: RE: st: Count observations per year; Next by Date: st: RE: Stata Technical Bulletin; Previous by thread: Re: st: Count observations per year; Next by thread: st: Stata Technical In general, I collapse the mean with standard deviation and count them together to take the number of observations and their variation into account. If * appears between two numeric values, Stata multiplies them. From: Joseph Monte <[email protected]> Re: st: Counting observations between dates by group. Example: The very first treated observation is matched with id 2. 3. 3 739943 1149175 Female 581590 82855. For example, if you wanted to count by 10s from 50 to 100 you would write: forval i = 50(10)100 { to start the loop. Nov 16, 2022 · I want to keep track of the number of distinct values seen so far in the sequence. In Stata terms, duplicates are observations with identical values, either on all variables if You would loop over observations: for each observation { compile a list of all the values of the string variables count the number of distinct values (not ". I used the following two lines of code: egen count_obsv = tag(loc_ID year) This adds a counter to my dataset (count_obsv) which is 1 (and 0 for every element that has the same combination of loc_ID and year) for every new combination. ) We also need an understanding that true and false conditions evaluate numerically for each observation { compile a list of all the values of the string variables count the number of distinct values (not ". Uses egen count() with by, to create two new variables recording the raw number of employed / unemployed people in the region. That is what we see below. The dept variable is missing in 9 observations and, farther down, the table reports that it is not missing in 116 observations. ucla. In the speech presentation attached in #7, What he refered to as faults, traps and clumsiness are still widespread in Stata. Can you help me with that? Thank you very much. Remarks and examples stata. ind == 1 for those observations in which the absolute difference is <= 2. (This might be a long list of identifiers or some other codes specifying which observations belong in the subset. Err. ) Having created the new variable dup, you could then . run) is missing, then we start (or restart) counting at 1; else we just continue counting. Counting specify value across Sep 15, 2023 · 在 Stata 中，您可以使用 `count` 命令来计算满足特定条件的观测数量。您可以使用 `if` 条件语句来指定条件。下面是一个示例： ``` count if condition ``` 在上面的命令中，您需要将 `condition` 替换为您要应用的条件。 4duplicates— Report, tag, or drop duplicate observations Remarks and examples stata. tabulate dup to see a report of the duplicate count. Jun 19, 2019 · 2. _n is called an “underscore variable”. To do this, you use the by prefix command. regards Krishanu On Feb 12, 2008 10:57 PM, Nick Cox <[email protected]> wrote: > Krishanu's code can be Re: st: Counting observations between dates by group. The second line sets the new variable miss to missing if any of the values of the independent variables are missing for that observation. Jul 22, 2019 · How to get the count of all observations in a table in Stata 13? 1. j. I could resolve that problem in the following way: If you want to count the occurrences of 0 in the values across x1-x3, then Nov 6, 2011 · This is an easy way to get see how many observations are in your dataset, but it can also count the number of observations based on a variable which groups observations. Counting distinct values: there was a survey of the terrain by Gary Longton and myself in SJ-8-4 dm0042 . count. The procedure is Aug 1, 2022 · How to count the number of observations in R like Stata command count. Count unique values in Stata. Best, Ben Ben Hoen LBNL Office: 845-758-1896 Cell: 718-812-7589 -----Original Message----- From: [email protected] [mailto: [email protected]] On Behalf Of Nick Cox Sent: Friday, January 06, 2012 10:47 AM To: [email protected] Subject: Re: st: Count of unique cases by [no]obs includes or suppresses only the reported number of observations from the table. _n basically indexes observations (rows): _n = 1 is the first row, _n = 2 is the second, and so on. The observed number of units is the default when exp is not specified. colmissing(X) returns the count of missing values of each column of X, rowmissing(X) returns the count of missing values of each row, and missing(X) returns the overall count. [95% Conf. I would like to count for each observation the number of variables that meet a certain condition, say var*==2. I tried the following code: Nov 10, 2014 · For each group, I have a varying number of observations. oarc. svy: mean computes the above variance and saves it in a matrix called e(V_srs). If you typed, perhaps by accident, . If the corresponding values differ, diff will be 1, and, if they are the same, diff will be 0. For this reason there can be multiple observations by person and year in the input file, in which each neighbor is a person with their own unique id. In this problem, the result is the same. Re: st: Estout and number of observations. Total estimation Number of obs = 4946 Male: sex = Male Female: sex = Female Over Total Std. 0. Each observations refers to an event that is specified with a date. (If there are 10 observations in a group, the last is obviously the 10th. From: "Ben Jann" <[email protected]> Re: st: Estout and number of observations. So, for example, a macro containing count specifies that # in sample # be interpreted as an observation count rather than as a percentage. counting • N is interpreted as the number of observations within each distinct group defined by by varlist:. Looking at the help of the command, it does not seem possible to store this value. . Any help is greatly appreciated. Computing the number of observations for subpopulation estimation can be tricky. Typing sample 5 without the count option means that a 5% sample be drawn; typing sample 5, count, however, would draw a sample of 5 observations. I have a dataset in Stata and want to count by group (loc_ID) and year. 4 System variables ( variables). If no conditions are specified, count displays the number of observations in the data. The Stata Journal (2007) 7, Number 4, pp. From: Nick Cox <[email protected]> Re: st: Counting observations between dates by group Say my dataset includes 10 observations and 10 variables, var101- var110. Start with the first column. ac. svy: mean also saves the number of observations in e(N). 571–581 Speaking Stata: Counting groups, especially panels Nicholas J. Adding a summary observation to a dataset will only lead to problems when you try to do analysis using that data. You can do the above by using by:, which is one of the most versatile features of Stata. Mar 5, 2021 · How I can count the number of missing (or NULL) values in distinct from 0 values? I have tried to use some functions listed below, but I don't know if these functions could distinguish the missing values from 0 values. It is the same logic. 4. 6. This is also apparent from the fact that different summary variables will need different names. Count the number of observations count As above, but where catvar equals 3 count if catvar==3 Count observations for each value of catvar by catvar: count Menu Data > Data utilities > Count observations satisfying condition Syntax count if in by is allowed; see[D] by. Stata determines by context whether * means multiplication or string duplication. If * appears between a string and a numeric value, Stata duplicates the string as many times as the numeric value indicates. We can also count missing values and use multiple conditions using " obs—Increasethenumberofobservationsinadataset Description Quickstart Syntax Remarksandexamples Alsosee Description Nov 16, 2022 · if the previous value (L. Sep 24, 2017 · I would like to have the count on the L side instead of the frequency as is depicted on the third graph. Jul 6, 2020 · Edit 1: There is a command to count the number of observations (rows), i. Here is an example of the data with ID, year, and the job code (i. See [no]means option above. Without any arguments, dups returns information on the number of groups of observations that have duplicates and the number of duplicates in each group. Interval] heartatk Male 944559 104372. The wordcount() or wordcount machinery has no sense whatever that the words it is counting are variable names. I've tried count and sum and all manner of "by" statements. The first table lists the variables, their storage type (type), the number of observations (obs), the number of missing values (mv), and the variable label if the variables has one. Learn how to count the number of observations in Stata using various methods and commands. collapse—Makedatasetofsummarystatistics Description Quickstart Menu Syntax Options Remarksandexamples Acknowledgment Alsosee Description 介绍了stata中egen函数count和anycount的使用方法，帮助用户更好地处理数据。 Under the protection of by:, subscripts apply to observations within each group. numlists have the form of one number or first/last. The solution. To illustrate, let’s use stocks. Positive numbers count from the beginning of the dataset. For bootstrap sampling of the observations, exp must be less than or equal to N (the number of observations in the data; see [U] 13. ) Hi r/stata, . Edit 2: I am terribly sorry for causing such ruckus over something simple. Suppose you have data on families. 1. glszabw onrip tiv gkzow yiau olag zcrzrq nzdgzp btb frpri rzrk osmzia rcafn zfrmit mgz