A BASIC program package for weighted least squares solutions using a microprocessor with disc memory.

The fitting of linear additive models to data by weighted least squares methods has been programmed in BASIC. By splitting up the matrix solution into several steps, the RAM memory space needed in a microprocessor by the corresponding programs was reduced, allowing room for larger matrices. Storage of intermediate products, and of subsequent programs in the sequence , was on a mini floppy dual-disc drive. Using an extended BASIC interpreter permitting several files to be open during a program, the program package compromised between computing time and problem size. Problems involving 1600 element matrices were run on a micro having 32000 bytes of memory, allowing for example, the fitting of a model with 22 parameters to 72 observations.