STATA 13 DATASETS FULL

Observations and take days or weeks to complete. Programs are run repeatedly on datasets with tens or hundreds of million Put into programming can pay dividends in faster results, especially when People waiting for computers are also expensive, and often a little thought It is a truism that computers are cheap and people are expensive. Suggestions for greatly reducing the run time for common operations in Stata. In this note we offer suggestions for doing theД®xtraction in Stata, eliminating the SAS step. In manyД¬ases a preliminary extraction has been done is SAS, followed by analysis ofДЄ smaller subset in Stata. Size, while Stata was limited to datasets that would fit in core. The considered the preserve of SAS, because SAS could handle datasets of any The analysis of very large files, such as health insurance claims, has long been This example exports the SAS data set SDF.CUSTOMER, to the Stata file, CUSTOMER.DTA, on a local system. Example 1: EXPORT a SAS Data Set to a Stata File on a Local System. export excel output.xlsx, firstrow(varlabels) sheet('output1') saves the dataset as an Excel file 'output.xlsx' to the sheet 'output1'.Stata for nearly big data Stata for very large datasets When exporting a SAS data set to a Stata file, SAS uses formats that are associated with the variables to retrieve the value entries. import excel filename.xls, firstrow loads the dataset with the original variable names. import excel filename.xlsx, clear loads the dataset but the variable names will be lost. Import/export excel reads/saves worksheets from Microsoft Excel (.xls and. We got the correct variable names, just in the wrong places. Here delimiters(space, collapse) collapsed the multiple spaces into just one. import delimited output.txt, rowrange(4:l) varnames(4) delimiters(space, collapse) What happened? Stata used multiple spaces as delimiters, and due to that values from one variable went to different columns. We had three variables, and now we've got a lot more (260! if we list them all). Now the first few empty rows have been removed and (some) variables are properly named. | ticker v2 v3 v4 v5 v6 evtdate v8 v9 v10 v11 v12 v13 car |Дў. delimiters(space) tells Stata to use space as the delimiters. varnames(4) means the fourth row is for the variable names. Rowrange(4:l) reads data from the fourth to the last row ( l stands for 'last'). import delimited output.txt, rowrange(4:l) varnames(4) delimiters(space) We can see that all variables are squeezed into one column 'v1', that there are empty rows, and that the variable names actually are the fourth row. Let's say we have a text file downloaded from a database and we tried to read it into Stata by Sometimes we need to take a few more steps to read a text file. export delimited output.txt, delimiter(tab) exports a file and saves it as a tab-delimited text file. Loads the dataset and names the three variables var1, var2 and var3. import delimited var1 var2 var3 using filename.csv, clear If the extension is not specified, Stata assumes that it is a. Import/export delimited reads/saves text-delimited files. sysuse auto, clear Read and save delimited text files (.csv. Sysuse loads example datasets installed with Stata We can also read a file over the Internet.

STATA 13 DATASETS FULL

To tell Stata to read a file elsewhere, we need to specify a full path. To load a file located in a subdirectory under the working directory, we need to specify the relative path. If such a file does not exist, we can skip the replace option. Replace overwrites the file saved earlier with the same file name. The analysis of very large files, such as health insurance claims, has long been the considered the preserve of SAS, because SAS could handle datasets of any size, while Stata was limited to datasets that would fit in core. Save filename, replace saves a Stata file to the current working directory. If the workspace is already clear, we can skip that as well. Use filename, clear loads a Stata file (.dta) from the current working directory.Д¬lear clears the memory for Stata to load a new file.

Stata will always go to the current working directory when working with files.

We may want to work with a file in Stata format as early as possible. Reading and writing Stata binary files is much faster than using text files. Reading and Saving Files of Various Types

Stata 13 datasets