04 Feb How Do I Create New Variables In Stata?

Stata is a powerful statistical software package that is widely used by researchers, analysts, and data scientists to analyze and manipulate data. One of the key features of Stata is its ability to create new variables from existing ones. In this article, we will discuss how to create new variables in Stata and some of the ways in which they can be used.

There are several ways to create new variables in Stata. The most basic way is to use the “generate” command. The syntax for this command is:

where “new_variable_name” is the name of the new variable you want to create, and “expression” is the formula or calculation that defines the values of the new variable. The expression can use any combination of Stata functions, operators, and existing variables.

For example, suppose you have a dataset that includes a variable called “age” and you want to create a new variable that is the square of the age. You could use the following command:

This would create a new variable called “age_squared” with the value of “age” squared for each observation.

You can also create new variables using conditional statements. For example, you might want to create a new variable that indicates whether an observation is above or below a certain threshold. To do this, you can use the “if” command in combination with the “generate” command. The syntax for this command is:

where “condition” is a logical expression that evaluates to true or false for each observation. If the condition is true, the new variable will be set to 1; otherwise, it will be set to missing.

For example, suppose you want to create a new variable called “high_income” that indicates whether an observation has an income above $100,000. You could use the following command:

This would create a new variable called “high_income” with a value of 1 for observations with an income greater than $100,000, and missing for all other observations.

Another way to create new variables is to use the “egen” command. This command allows you to perform a variety of calculations on groups of observations, such as computing the mean or standard deviation of a variable within each group. The syntax for the “egen” command is:

where “function” is the name of the Stata function you want to apply to the variable, “variable_name” is the name of the variable you want to calculate the function for, and “group_variable_name” is the name of the variable that defines the groups.

For example, suppose you have a dataset that includes a variable called “region” that indicates the geographic region of each observation, and you want to create a new variable that indicates the mean income for each region. You could use the following command:

This would create a new variable called “mean_income_by_region” with the mean income for each region.

In addition to these basic methods, Stata offers many other ways to create new variables, including merging datasets, reshaping data, and using programming techniques. With practice and experimentation, you can learn to use Stata’s powerful tools to create new variables that suit your specific analytical needs.