pollution data;  truncation of data;  Contamination factor

Let X1,X2,...,Xn be a list of non-negative independent random variables with the same distribution, and its distribution is: Fα(x)=(1-α)F1(x)+αF2(x), where α∈[0,1], F1(x),F2(x) are all distribution functions defined on R+, now Y1, Y2,..., Yn are non-negative i.i.d~G(t) truncated random variable columns, and Xi and Yi are also independent of each other, and it can only be observed that Zi=min(Xi,Yi),δi=I( In the case of Xi≤Yi)(i=1,2,...,n), an estimate of the pollution coefficient α is given, and its compatibility is proved when G(t) is known.