Prepare data online

Use the Prepare Data page to clean, transform, combine, and weight variables before running a statistical analysis. Choose a preparation type, select the variables to process, enter the required settings, name the result, and add the newly prepared variable or variables to your data table. The original variables remain available, so you can compare them with the prepared data.

Data preparation options

• Recoding: Convert a single value, a range of values, or invalid entries into new numeric values or invalid entries. Use this to group values into categories, reverse-code a scale, or define missing values.
• Sum/Mean Score: Combine multiple variables into a row-wise sum score or mean score. You can also set the minimum number of valid values required to calculate the score.
• Outliers: Identify and exclude extreme values from a metric variable using manual limits, the 1.5 × IQR rule, a z-score rule of mean ± 3 standard deviations, Grubbs' test, or Dixon's Q test. A preview shows the affected rows and values before you create the new variable.
• If-Then: Create a new variable from combinations of values in two existing variables. Enter the two input values and the numeric value that the matching combination should become.
• Box-Cox Transformation: Transform a metric variable to improve normality. The page estimates lambda, displays the distribution and normality results before and after transformation, reports the 95% confidence interval, and can use a rounded lambda when it lies within that interval.
• Weighting: Apply a weighting-factor variable to one or more selected variables. The factor can be multiplied by a specified value; non-integer weights are rounded when observations are replicated.

How to prepare your data

1. Load or enter your data in the data table.
2. Select the required preparation type at the top of this page.
3. Select the source variable or variables and configure the displayed options.
4. Review any preview, limits, test results, or transformed distribution.
5. Enter a clear name for the new variable and select Add or Create New Variables.
6. Use the new variable in descriptive statistics, charts, or further analyses.