1. The document describes the features included in the base package and add-on packages for IBM SPSS Statistics Subscription.
2. The base package includes data access and management, data preparation, graphs, output, help features, data editor enhancements, and statistics features.
3. There are three add-on packages that can be purchased in addition to the base package: Custom Tables and Advanced Statistics, Complex Sampling and Testing, and Forecasting and Decision Trees. Each add-on package provides additional advanced analytical features.