An analysis of models for the dilution and adulteration of fruit juice

We present models based on the multivariate normal distribution to represent the process of dilution and adulteration of citrius juice. The models specify a common dilution parameter for those components of the juice which are affected by dilution but not adulteration. Statistical testing of the hypothesis of no dilution or adulteration presents theoretical difficulties. These difficulties are resolved by model comparisons based on averaged, rather than maximized, likelihoods.