Firms within the food supply chain must decide what information to provide and how to provide it. This applies to collecting information from upstream suppliers as well as to supplying information to downstream customers. Components of this vertical information situation include farmer supplier...

We introduce the stratified sampling method, and put forward theoretical unbiased estimation of stratified sampling program, as well as the model and statistics of experimental design test. We also discuss the establishment of dietary exposure model, pollutant distribution model, and risk...