Popis: |
An interactive microcomputer-based routine was developed for trend surface analysis. The routine includes robust alternatives, along with the more typical least-squares procedure, and provides graphical as well as statistical output. The robust procedures are suitable for data that do not meet the assumptions implicit in the least-squares procedures, and can also be used for outlier detection. The routine was developed in the DOS environment, which makes it very portable. It allows for interactive data entry and the selective removal of trend surface coefficients. The use of the routine is demonstrated on several data sets. |