This manuscript deals with new class of almost unbiased ratio cum product estimators for the estimation of population mean of the study variable by using the known values auxiliary variable. The bias and mean squared ...This manuscript deals with new class of almost unbiased ratio cum product estimators for the estimation of population mean of the study variable by using the known values auxiliary variable. The bias and mean squared error of proposed estimators are obtained. An empirical study is carried out to assess the efficiency of proposed estimators over the existing estimators with the help of some known natural populations and it shows that the proposed estimators are almost unbiased and it perform better than the existing estimators.展开更多
Based on the study of ancient maps preserved in China and abroad,the systematic nature and practical meaning of the maps of the Yellow River and Grand Canal is demonstrated.It is pointed out that the ancient maps not ...Based on the study of ancient maps preserved in China and abroad,the systematic nature and practical meaning of the maps of the Yellow River and Grand Canal is demonstrated.It is pointed out that the ancient maps not only record the spatial information of the established water conservancy engineering for river harnessing but also the management systems of the rivers in history.Besides,the maps provide abundant information on nature,humanity,and geography and possess high value in academic research and art appreciation.展开更多
文摘This manuscript deals with new class of almost unbiased ratio cum product estimators for the estimation of population mean of the study variable by using the known values auxiliary variable. The bias and mean squared error of proposed estimators are obtained. An empirical study is carried out to assess the efficiency of proposed estimators over the existing estimators with the help of some known natural populations and it shows that the proposed estimators are almost unbiased and it perform better than the existing estimators.
文摘Based on the study of ancient maps preserved in China and abroad,the systematic nature and practical meaning of the maps of the Yellow River and Grand Canal is demonstrated.It is pointed out that the ancient maps not only record the spatial information of the established water conservancy engineering for river harnessing but also the management systems of the rivers in history.Besides,the maps provide abundant information on nature,humanity,and geography and possess high value in academic research and art appreciation.
