On the basis of researches on the world-wide probe vehicles sample size for mobile traffic detection system,authors analyzed shortcomings of existing products.

Analysing the relationship between the correlation degree, the precision, the sample size in regression forecast, two models are obtained.

An optimization method for the minimum probe vehicles sample size of urban road network in mobile traffic detection system was proposed.

Since there is very little literature about the review of the study for determining probe vehicle minimum sample size,the probe vehicle minimum sample size methods were summarized in the first,then the feasibility of different methods for demands of the traffic parameter estimation was analyzed,and finally the further research direction for determining probe vehicle minimum sample size was given.

Using variance revising method to determine sample capacity in partial estimation;

By way of the indentification of total receiving sample principle, it obtains the inspecting criterion So of the masses of coal separation products and the sample capacity that should be taken out .

First,in combination with the national Standards,the influence of “two errors”exsiting in the project quality control on the valuing of sample capacity is analysed.