Global Journal of Science Frontier Research, F: Mathematics and Decision Science, Volume 21 Issue 4

� � � = { ( )} −2 4 �� 1 − 1 � + � 1 − 1 ′ � � ( ) ( ) � �� { ( ) { ( ) � − 2 �� (21) Singh, Singh, and Upadhyay (2007) studied a ratio-type estimator of median using two auxiliary variables � = � � � ′ � � 1 � � ′ � 2 � � � 3 Where 1 = � { ( ) { ( ) � � − 2 −1 � , 2 = � { ( ) { ( ) � � − 2 −1 � , 3 = � { ( ) { ( ) � � − 2 −1 � � � � ≅ { ( )} −2 8 �1 − 2 � 2 �� 1 − 1 ′ � �1 − 2 � �� − � 2 − 2 � − � + � { ( ) { ( ) � � − �� + � 1 − 1 � � − � �� − � + 2 � − � + � { ( ) { ( ) � �1 − 2 �� + � 1 ′ − 1 � � − � � 2 � − � − 2 �1 − 2 � + � { ( ) { ( ) � �1 − 2 ��� � � � ≅ { ( )} −2 4 �� 1 − 1 � − � 1 ′ − 1 � 2 − � 1 − 1 ′ � 2 + 2 −2 �1− 2 � � (22) ii) Jhajj, Kaur, and Jhajj (2016) defined ratio-exponential-type estimator as � = � � � ′ � 1 � � � 2 �� 3 � � − � � + � � �� Towards the Efficiency of the Ratio Estimator for Population Median in Survey Sampling © 2021 Global Journals 1 Global Journal of Science Frontier Research Volume XXI Issue IV Year 2021 44 ( F ) Version I N otes