The Windows, Macintosh and DOS versions feature an interactive editor that allows you to create, test, and run RATS programs; view, save, and print text and graphs; access on-line help; and much more. While running in interactive mode, you can quickly experiment with different models or procedures, without having to repeat earlier steps each time.

All versions of RATS also offer batch mode operation. In batch mode, RATS automatically reads and executes instructions from one or more input files, and saves the output to disk.

Statistical Features

Estimation Techniques

• Multiple regressions, including stepwise
  
• Regressions with autoregressive errors
  
• Regressions with heteroscedasticity correction
  
• Seemingly unrelated regressions and three-stage least squares
  
• Non-linear least squares
  
• Two-stage least squares for linear, non-linear, and autocorrelated models
  
• Maximum likelihood estimation, supporting a wide variety of problems including ARCH, GARCH and related models. Supports multivariate likelihood functions, and offers a simplex estimation method for non-differentiable functions
  
• Non-linear systems estimation
  
• Generalized Method of Moments
  
• Constrained optimization (Version 5.0)
  
• Built-in hypothesis testing instructions
  
• Logit and probit
  
• Fixed/random effects estimators (Version 5.0)
  
• Consistent covariance matrices, including "White" and "Newey-West"
  
• State-space models (Version 5.0)
  
• Neural Network models
  
• Linear/Quadratic programming
  
• Kernel density estimation (Version 5.0)

Time Series Procedures

• ARIMA models including multiplicative seasonal models (supports arbitrary lag structures)
  
• Vector autoregressions
  
• Impulse responses
  
• Variance decompositions
  
• Structural VAR's (Version 5.0)
  
• Error Correction Models (Version 5.0)
  
• Kalman filter for sequential estimation
  
• Transfer functions
  
• Intervention models
  
• Spectral analysis
  

Forecasting

• Time series models
  
• Regression models
  
• Exponential smoothing
  
• Simultaneous equation models (supports unlimited number of equations)
  
• Simulations with random or user-supplied shocks
  
• Forecast performance statistics

Other Features

Graphics

• Line, symbol, bar, stacked bar and filled graphs for time series
  
• Dot, symbol, line, bar and filled X-Y graphs
  
• Dual-scale (overlay) time series graphs and (Version 5.0) X-Y graphs
  
• Arrays of graphs on a page
  
• Log scales (Version 5.0)
  
• Exports graphs to PostScript, HPGL, PIC, Windows Metafile, and Macintosh PICT
  
• Export can be done automatically, as graphs are produced (Version 5.0)
  

Data Entry

• Reads and writes ASCII, DIF, PRN, DBF and binary files
  
• Reads and writes Lotus Worksheet (including WK3) and Excel XLS spreadsheet files
  
• Write HTML tables (Version 5.0)
  
• Supports our own RATS data file format, which is fast and easy, supports all frequencies, and allows mixing of frequencies on a single file
  
• RATS format now portable across DOS, Windows, Macintosh, and UNIX platforms
  
• On-screen data editor
  
• Menu-driven RATSDATA utility program for maintaining, graphing, importing, and exporting data
  
• Can handle virtually any data frequency, including daily, weekly, intra-day, and panel data
  
• Easily converts among different data frequencies
  

Data Transformations

• Flexible transformations with algebraic formulas
  
• Easy to create trend series, seasonal, and time period dummy variables
  
• Specialized differencing and filter operations