Tuesday, December 18, 2012
Computational Back Engines
The software implementation of Vilno Table is (mostly) a front end, it needs to be connected to two computational back engines: one engine for data transformation, data preparation, and summary statistics and the other engine for advanced statistical procedures (linear model, survival analysis, etc.).
The front end, a "conceptual compiler", controls the two computational back engines: giving them lower level code files (that the worker does not have to look at) to execute and gathering the results to put in a statistical table.
The choices for the data transformation back engine include:
1. Vilno Data Transformation (VDT). A low-cost open source replacement for the SAS datastep (as well as proc transpose, proc means, and proc sql (for many-to-many joins))
2. SAS/BASE (SAS datastep, proc sql, proc transpose, proc means)
3. SPSS (possibly), depending on demand
4. others , depending on demand
The choices for the statistical procedure back engine include
1. S programming language implementation (R or S-Plus)
2. SAS/STAT (procedures for linear model, survival analysis, etc.)
3. SPSS, depending on demand
4. others, depending on demand
At this time, the current implementation of Vilno Table uses low-cost choices for the computational back engines: VDT and R. (Remember: the worker does not have to write or read any VDT code or R code to produce statistical tables, Vilno Table does that work under the hood.)
Also, when a later version of Vilno Table is configured to two or three statistical procedure back engines (at the same time, on the same hard drive), which is very doable, then you can easily do a statistical table with p-values and other statistics from R and S-Plus and SAS/STAT, all on the same page.