Create a Dataset

SpaceStat allows you to create new datasets from existing datasets. This can be done through statistical methods, through standardization, or through using the dataset calculator to make a custom dataset, such as a threshold dataset (illustrated below) or a difference dataset.

To calculate a new custom dataset, go to the "Tools" pulldown menu and select " Derive new dataset."

The dataset calculator will appear, shown below. First, you name your new dataset and select the appropriate geography for the dataset(s) which will be used to create the new dataset . To specify how you would like the existing dataset to be modified, type a mathematical expression in the box titled "dataset definition."  You can type standard symbols (e.g., +, -), or choose functions from the pull-down menu in the lower right corner labeled "insert function."  The new derived dataset will have values at all of the times included in the original dataset, so, as with other datasets, you can animate views of derived datasets and synchronize these animations with data in other views.

The syntax for identifying datasets to be modified is to precede the dataset name by a $, surround it in parentheses, and include the name in quotation marks. This syntax encapsulates the dataset name so that it isn't interpreted as part of a mathematical expression, even if the name includes mathematical symbols. SpaceStat automatically adds this syntax if you select datasets from the drop-down menu at the lower left. Thus, in the example below, our new dataset will be categorical, with RWM (rates for white males) values greater than 1.5 coded as "high", and other rates coded as "low."  To see two more examples of dataset definitions, including one that involves using values for the same dataset at different times in the calculation, go to the Difference Dataset page.