等量资本获得等量利润质疑

The classical economists and Marx believed that the same amount of capital could gain the same amount of profit． This is largely limited
by the analysis of assumed data and has not been proved by survey data． Based on the survey data that we gain from worldwide，we find that actually the
profit margin from different department is not same． The actual profit margin is influenced by different factors; some of the factors cause an average of profit
margin，while other factors cause an non-average． These two factors might be partly offset． The factor that causes the non-average is stronger and may
include the motives and behavior of the enterprise to pursuit profit maximization，the different labor quality and production cost of the different departments，
the incompleteness of the information，the offset between the demand changes and the supply changes． All these factors bring a combined effect
which makes the same amount capital invested in different departments unlikely to obtain the same amount of profit．