Sampling American Cotton -- Prevailing Practices and Some Factors Affecting Representativeness of Samples

Excerpts from the report Introduction: Reliable classification of cotton requires that samples be adequately representative of the bales from which they are drawn. The manner of drawing the sample and other factors affecting its representativeness deserve more consideration than they have received. The importance of a properly drawn sample is too little recognized either by the one who draws the sample or by those who handle it before it is used as the basis of classification. This report presents information assembled through a recent study of various methods of sampling cotton in the United States and of closely related practices insofar as they are associated with representativeness of the samples drawn. It is known that disparities can and do occur in the classification of samples from the same bales of cotton by different classers. As presumably such disparities may be due in part to differences in samples, this study was made by the Bureau of Agricultural Economics to obtain information concerning the influence of different methods of sampling cotton and of closely associated practices on the representativeness of samples drawn. Consideration was given not only to the different methods of drawing samples from cotton bales and the distinguishing characteristics of the different types of samples, but also to (a) ginning and baling practices that affect representativeness of samples, such as plating of bales at the gin, and (b) handling of samples after they are drawn, such as trimming, rolling, and packing. These factors have an important bearing upon the proper classification of cotton bales. It is possible that comparison of the different methods of sampling employed in the different parts of the country, and of handling and caring for them after they have been drawn, might lead to better and more uniform practices.