After that you specify the word kernel that the multiple columns we want to reshape have in common. If you supply neither, melt will assume factor and character variables are id variables, and all others are. This tool allows you to transpose your column headers so that they now become rows horizontal to vertical. As part of the reshape command we create a variable called seq which will be the sequence identifier for the nine observations within each subject. These examples take long data files and reshape them into wide form. How to reshape data wide to long using proc transpose. Reshape from long to wide format with spread reshape from wide to long format with gather reshaping data between long and wide forms.
How can i reshape without a unique j variable in stata. Observations with information on the same variables are stored. When stata does not recognize text from numbers go to data editor and delete observation 1. In some cases, you may have to apply reshape twice to solve a particularly knotty data management. Many do not realize that the world bank databank has advanced download options that let you select the long format from the beginning. If you are downloading more than one series, however, you will still need to reshape the data a bit to get separate columns for each series. Id like to reshape a long format data file to wide. There are separate columns for each year, but you actually want the year to be a variable of its own.
This leads to difficulttoread nested functions andor choppy code. As an example, consider the data below presented in both formats the data itself is identical, but organized in a different way. In order to do this, you will use the reshape command, specifying that youre reshaping to the long format. This learning module illustrates how to reshape data files in spss versions 11 and up. In long format there will be multiple records for each individual, with some variables being constant across these records and others varying across the records. If more than one record matches, the first will be taken with a warning. Although the builtin reshape procedure in stata is invaluable for working with panel data, it is known to perform poorly on large datasets see this benchmark and this discussion. Reshaping data long to wide in versions 11 and up spss.
This video introduces the reshape command in stata. Your problem can be solved with a judicious use of order. The following example data contains two participants measured on two outcome variables weight and calories, under three different time points. How to perform a multiple regression analysis in stata. These show common examples of reshaping data, but do not exhaustively demonstrate the different kinds of data reshaping that you could enco.
In the results table, time is omitted due to collinearity and my rsquared figure is only 0. Hence, taking a dataset from long to wide and back to long will result in getting the same dataset labelling back again. The default download settings indicate missing values with two periods, like so. It also allows an arbitrary number of grouping by variables. We are here to help, but wont do your homework or help you pirate software. The long format uses multiple rows for each observation or participant.
Both post were about datastream, but one was about regular downloads and one about large datasets. Reshape in r from wide to long and from long to wide. Notice that the order of variables in varying is like x. Each variable has a different number of iterations, that is, one variable has four iterations, the variable has 7 iterations and so on. Stata offers the reshape command for restructuring data. Thus the variable names inc60, inc70, inc80, and inc90 all share the stubname inc. Jan 18, 2016 reshape the data long so that r and stata form their own columns and can be sorted by year hint. Converting a dataset from wide to long i recently had to convert a dataset that i was working with from a wide format to a long format for my analysis.
If you need to modify the structure of your data, you should surely be familiar with reshape and its two functions. The following example is taken from d reshape the official stata data management manual and involves multiple levels of sorting variables. One of the key data management tools stata provides is reshape d reshape. Below, is the data displayed in the longest possible format it will download in.
Im running into some issues while trying to reshape a data set from long to wide. The reshape command can be used to reshape from wide to long or long to wide. To reshape a wide data set long, you have to specify reshape long. To use the reshape command, the variables have to start with the same prefix. I struggled with this a bit, but finally found the right sources and the right package to do it, so i thought id share my practical example of reshaping data in r. Each unique variable should have a column, as well as corresponding columns of value, error, and unit, for each. Hello everybody, i need to reshape wide data to long. Here i am using the posted subset of your data, where you have time variables 1, 2, and 43. Hierarchical data is any kind of data where observations fall into groups or clusters. A long format dataset also needs a time variable identifying which time point each record comes from and an id variable showing which records refer to the same. Statalist reshape long and variables not being found. Stata s reshape command makes it easy to transform your data from either long to wide format or from wide to long. R studio is driving a lot of new packages to collate data management tasks and better integrate them with other. For this example, the variables for each case, are as follows.
This variable annotation allows us to separate the face variable into two. I have multiple variables within the dataset that i would like to do this for. I then create an interaction variable between the two. These show common examples of reshaping data, but do not exhaustively demonstrate the different kinds of data reshaping that you could encounter. We could melt and cast with reshape2 to reshape from wide to long format, but is there a way to reshape using even less code. The stata reshape command can convert the data files between these two formats. But stata records missing values as a single period. From the first output of proc print, we see that the data now is in long format except that we dont have a numeric variable indicating year. Hello, my data set is compose of adolescents and their parents and is currently in wide format. Reshaping data in stata wide to long and long to wide. This naming scheme tells stata that theyre different observations of the same variable. As described in the benchmarks section below, wideto long reshapes are between 2 and 15 times. Hi, kit your procedure for my reshape problem works almost perfect, the thing is that my descriptor usually is a very long string such as total factor productivity and when i do. Reed college stata help reshaping your data in stata.
In two previous posts i showed examples on how to reshape data from wide to long format. An example of reshape long with stata1 stata has reshape long and reshape wide commands that make it pretty easy to modify files from wide to long, and back. Reshaping multiple variables in one dataset using stata. These variables may also be present in wide format. In addition, we are often interested in combining multiple observations. Luckily for us, hadley wickham has created the easy to use tidyr. I already tried doing making a j variable and reshaping, using the following code. The stata reshape command apparently relies on this naming.
The egen command is very helpful many more functions are available, see help egen. Stata solution to reshape factset data researchfinancial. Now we can go ahead and reshape the data from wide to long with id as the subject identifier. The basic command reshape is followed by which direction long or wide you want to reshape the data. We are starting with the worksheet initial download. Reshaping data from wide to long university of virginia. If your variables were, for instance, hap1, happy2 and hap3, you would rename happy2 hap2 and then proceed. These show common examples of reshaping data, but do not exhaustively demonstrate the different kinds of data reshaping. Common examples of reshaping data are shown, but they do not exhaustively demonstrate the different kinds of data reshaping that you could encounter.
How can i reshape doubly or triply wide data to long. This handson tutorial shows how to reshape data from wide to longitudinal format in stata. This data layout is called wide data, but you want your data to be long. Although many fundamental data processing functions exist in r, they have been a bit convoluted to date and have lacked consistent coding and the ability to easily flow together. The command is useful when needing to change a dataset from wide format to long format. R language reshape from long to wide format with spread.
The option string says that the j variable is a string variable. Stata s datamanagement commands give you complete control of all types of data. This module illustrates the power and simplicity of stata in its ability to reshape data files. Reshaping your data with tidyr uc business analytics r. You will need to use the, string option when reshaping. Click here to download these lines of data to play with. These examples take wide data files and reshape them into long form.
Description of basic syntax wide and long data forms avoiding and correcting mistakes reshape long and reshape wide without arguments missing variables advanced issues with basic syntax. Mar 04, 2014 this video introduces the reshape command in stata. At a glance, i would guess that order personid a b c will arrange your vars as desired. Then, after having ordered alphabetically the variables thanks to aorder, it is asked to the software to create two new variables for each outcome included in the local macro and to generate. A key point is that in reshaping from wide to long, reshape expects to find one or more groups of variables so that names in each group all begin with the same stubname. In some cases, there is more than one way to reshape the data. These show common examples of reshaping data but do not exhaustively demonstrate the different kinds of data reshaping that you. For a data set in wide format such as the one below, we can reshape it into long format using proc transpose. Reshaping data sets from wide to long and from long to wide in stata.
The syntax is reshape long wide stubname, ii jj where the stubname is the stub of your variables in this case, it is cond, i is the id variable and j is the new variable youll create or the existing variable if reshaping. Reshaping data long to wide stata learning modules. You can work with byte, integer, long, float, double, and string variables. Stata news, code tips and tricks, questions, and discussion.
We can also use reshape to manipulate small segments of the data that are panellike. Names of one or more variables in long format that identify multiple records from the same groupindividual. Stata module to reshape while preserving variable labels reshape8 improves reshape by preserving variable labels as much as possible when switching back and forth. Mar, 2015 the first loop tells stata to use the datasets stored in the local macro and to reshape the selected outcomes from wide to long and then go back to wide. The most common examples at the sscc are individuals living in a household and a subject being observed multiple times, but there are many other applications. When going from wide to long, there are some labels which are not defined. Note that another column has been added to show the year.
How to use the stata merge and reshape commands most of the projects done in 17. The syntax diagram for the command in the manual and in the online help gives patterns for the socalled basic. Multiple regression an extension of simple linear regression is used to predict the value of a dependent variable also known as an outcome variable based on the value of two or more independent variables also known as predictor variables. You need to tell melt which of your variables are id variables, and which are measured variables. Useful stata commands for longitudinal data analysis. Stata requires the variables over which we perform the reshape command to be numbers rather than string. It also allows an arbitrary number of grouping by variables i and keys j. The issue is that i have two variables, but they arent both in the wide format.
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