英文文献：Use Of Ratios And Gross Margins In Time Series Supply Analysis
英文文献作者：Ferris, John N.
英文文献摘要：
Gross margins provide a means to (1) incorporate more a priority information into time series supply analysis and (2) consolidate two or more variables into one. Implicit in applying ratios are certain restrictive assumptions. The statistical fit of "gross margin" equations on five commodities compared favorably wi.th "ratio" and "separate variable" formulations.