In this thesis the measurement of the inclusive b-jet cross section is presented. The analysis was done with very early CMS data with an integrated luminosity of 60/nb. Furthermore this thesis presents the measurements on the b-jet purity for an update of the recent CMS analysis to 36/pb. For the update a new b-tagging as well as new statistical methods based on NeuroBayes were developed. New applications of the sPlot method, neural network boosting and data based training are presented.