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Multifactor productivity (MFP) measures the changes in output per unit of combined inputs. Indexes of MFP are produced for the private business, private nonfarm business, and manufacturing sectors of the economy. MFP is also developed for 2-and 3-digit Standard Industrial Classification (SIC) thru 1987, and NAICS (North Atlantic Industrial Classification System) thru 2005 for manufacturing industries, the railroad transportation industry, the air transportation industry, and the utility and gas industry.

Multifactor productivity measures reflect output per unit of some combined set of inputs. A change in multifactor productivity reflects the change in output that cannot be accounted for by the change in combined inputs. As a result, multifactor productivity measures reflect the joint effects of many factors including new technologies, economies of scale, managerial skill, and changes in the organization of production.

Whereas labor productivity measures the output per unit of labor input, multifactor productivity looks at a combination of production inputs (or factors): labor, materials, and capital. In theory, it’s a more comprehensive measure than labor productivity, but it’s also more difficult to calculate.

用SPSS做方差分析，检验ABCD四种分泌物对植物重量的影响。

XY即为实验结果。

ABCD为因素，用但因素方差分析就可以检验出四种分泌物的作用是否有显著差异。

如果有显著差异，再通过均值检验找到作用最大分泌物的即可。