Communications on Applied Nonlinear Analysis ISSN: 1074-133X Vol 32 No. 10s (2025) 1388 https://internationalpubls.com An Exponential Class Estimator of Mean in the Presence of Correlated Measurement Error under Systematic Sampling Technique Dr. Jamohan Singh Dhakar1, Dr Sanjay Jain2, Dr. Neha Singh3, Awadhesh Pandey4 1Assistant Professor (Statistics), Department of Community Medicine, Virendra Kumar Sakhlecha Government Medical College, Neemuch, MP, India 2Professor, Department of Statistics, St. John’s college, Agra, UP, India 3Assistant Professor, Department of Mathematics, Amrita Vishwa Vidyapeetham, Coimbatore, Tamil Nadu, India 4Department of Applied Sciences (Mathematics), Ananad Enginnering College, Agra, India Corresponding Author: Dr. Jamohan Singh Dhakar,Mail id : jagmohansinghdhakar@gmail.com Article History: Received: 12-01-2025 Revised: 15-02-2025 Accepted: 01-03-2025 Abstract: In this manuscript, an exponential class of estimators is proposed to estimate the average of the population by using auxiliary variables in the presence of measurement error (me ) as well as correlated measurement error (cme). The estimation for the average is done for the systematic sampling technique. The impact me and cme on the mse of the estimators is obtained in terms of mean square error (mse) and bias. The mean square error is also obtained for the ratio, product and regression estimator under correlated measurement error. To validate the results of the theoretical findings simulation studies is done by using R programming. Keywords: Mean, Mean Square Error, Bias, Systematic Sampling, Measurement Error, Correlated Measurement Error. Introduction Cochran (1977), Murthy (1967), Sukhatme et. al. (1984) have described all the literatures and theory about sampling techniques. Systematic sampling can be used where the population are natural population, for instances selection of every nth person visiting to a shopping mall, selection of a person from the list of any city or place, selection of fields from any geographical location. Cochran(1946) provided certain situations where systematic sampling is more efficient in comparison to simple random sampling and stratified sampling. Gautschi (1957), Meadow (1949, 1953) are legends in the literature of systematic sampling. Lahiri (1954), and Williams (1956) have done remarkable work in the systematic sampling. Auxiliary information is used to obtain better efficiency in terms of precision and to reduce the cost of survey. For instance, in the estimation of the crop, temperature fertilizer, irrigation can be considered as amount auxiliary information. To estimate the income of any place, the expenditure and different sources of income can be considered as auxiliary variable. Murthy (1964) addressed the conditions under which the estimations techniques ratio, product and unbiased estimators can be Communications on Applied Nonlinear Analysis ISSN: 1074-133X Vol 32 No. 10s (2025) 1389 https://internationalpubls.com efficiently used. Use of auxiliary variable in context of systematic sampling was done by Swain (1964). As he shown that systematic sampling is very efficient for estimation of volume of timber where auxiliary information can be taken as area of the leaf or the tree’s girth as suggested by in introducing ratio estimator for systematic sampling. The product estimator for systematic sampling was introduce by Shukla (1971). Measurement error is the contamination commingled in data during the survey or during the compilation of the data. Shalabh (1997) addressed the impact of measurement error in ratio estimation for simple random sampling. Singh et. al. (2019) proposed an efficient variant of the ratio, product and mean estimator in the presence of measurement error. The assumption of measurement error in the previous literature of the study variable π‘Œ and auxiliary variable 𝑋 are uncorrelated. The measurement errors of the study variable π‘Œ and auxiliary variable 𝑋 may be correlated with each other as the same person or same instrument are used to collect the information for both variables. Shalabh and Tsai (2017) first introduce the correlated measurement error with reference to ratio, product regression estimator. Further Singh and Vishwakarma (2019) studied about measurement error. Singh and Vishwakarma (2020) introduce measurement error in the context of systematic sampling. They provided mean square error for ratio estimator, product estimator and regression estimator in the presence of measurement error for systematic sampling. In pre- existing literature, only Singh and Vishwakarma (2020) have addressed the measurement error in context of systematic sampling. Also, no any studied is done for correlated measurement error in context of systematic sampling. By considering, the wide applicability of systematic sampling and following above literature, in this manuscript, a well-known exponential estimator is proposed to obtain the effect of measurement error as well as correlated measurement error on mean square error. The mean square error is also derived for well-known namely ratio and product estimator in the presence of correlated measurement error under systematic sampling. For systematic sampling, the population of size 𝑁 is divided into π‘˜ intervals such that 𝑁 = π‘›π‘˜. Sample of size 𝑛 is selected through systematic sampling. As first unit is selected at random from the first π‘˜ units. If the first unit is the 𝑖th unit of the first π‘˜ units the second unit of the sample is the 𝑖 + π‘˜th unit of the second π‘˜ units. Similarly, other units of the samples are selected. After sampling of 𝑛 units are done through systematic sampling we observe the study and auxiliary variables. It is considered that a situation where each data of the study and auxiliary variable are observed with error. Let us assume (π‘₯𝑖𝑗 , 𝑦𝑖𝑗) be the observed values and their true values are (𝑋𝑖𝑗, π‘Œπ‘–π‘—) where the subscript 𝑖𝑗 represents 𝑗th unit of the 𝑖th interval and 𝑖 = 1,2, … , π‘˜ and 𝑗 = 1,2, … , 𝑛. As the observed values are with errors they can be represented in the following form, π‘₯𝑖𝑗 = 𝑋𝑖𝑗 + 𝑉𝑖𝑗 and 𝑦𝑖𝑗 = π‘Œπ‘–π‘— + π‘ˆπ‘–π‘— and (π‘ˆ, 𝑉) represent the errors. The errors (π‘ˆ, 𝑉) are normally distributed with mean zero and variance (πœŽπ‘ˆ 2, πœŽπ‘‰ 2). Let us assume that the error variables π‘ˆ and 𝑉 are correlated to each other and a they are uncorrelated to all the combination with the study and auxiliary variables 𝑋 and π‘Œ. From the before mentioned assumptions we obtain πΆπ‘œπ‘£(𝑋, π‘ˆ) = πΆπ‘œπ‘£(π‘Œ, π‘ˆ) = πΆπ‘œπ‘£(𝑋, 𝑉) = πΆπ‘œπ‘£(π‘Œ, 𝑉) = 0 and Communications on Applied Nonlinear Analysis ISSN: 1074-133X Vol 32 No. 10s (2025) 1390 https://internationalpubls.com πΆπ‘œπ‘£(π‘ˆ, 𝑉) = πΆπ‘œπ‘£(𝑋, π‘Œ) β‰  0. Let πœ‡π‘‹π‘ π‘¦, πœ‡π‘Œπ‘ π‘¦ be the population mean of the auxiliary and study variable respectively and let πœŽπ‘Œπ‘ π‘¦ 2 , πœŽπ‘‹π‘ π‘¦ 2 be the population variance of the study and auxiliary variable respectively. Let 𝜌 be the correlation coefficient between the study and auxiliary variable. Let the sample means of the true values of the study auxiliary and study variable be �̅�𝑠𝑦, �̅�𝑠𝑦 respectively. The unbiased estimators of the population of mean of the study and auxiliary variables are the sample means of the observed data. The unbiased estimators of the population are as follows, οΏ½Μ‚οΏ½π‘Œπ‘ π‘¦ = οΏ½Μ…οΏ½π‘˜π‘ π‘¦ = 1 𝑛 βˆ‘ 𝑦𝑖𝑗 𝑛 𝑖=1 , 𝑖 = 1,2, … , π‘˜. (1.1) �̂�𝑋𝑠𝑦 = οΏ½Μ…οΏ½π‘˜π‘ π‘¦ = 1 𝑛 βˆ‘ π‘₯𝑖𝑗 𝑛 𝑖=1 , 𝑖 = 1,2, … , π‘˜. (1.2) To obtain the bias and variance we can write the error term πœ€π‘‹ , πœ€π‘Œ as follows, πœ€π‘‹ = οΏ½Μ…οΏ½π‘ π‘¦βˆ’πœ‡π‘₯𝑠𝑦 πœ‡π‘₯𝑠𝑦 , πœ€π‘Œ = οΏ½Μ…οΏ½π‘ π‘¦βˆ’πœ‡π‘Œπ‘ π‘¦ πœ‡π‘Œπ‘ π‘¦ As �̅�𝑠𝑦 and �̅�𝑠𝑦 are unbiased estimators of οΏ½Μ‚οΏ½π‘Œπ‘ π‘¦ and �̂�𝑋𝑠𝑦 respectively we can write 𝐸(πœ€π‘Œ) = 𝐸(πœ€π‘‹) = 0, �̅�𝑖. = �̅�𝑠𝑦 = 1 𝑛 βˆ‘ π‘ˆπ‘› 𝑗=1 𝑖𝑗 , 𝐸(πœ€π‘‹ 2) = 1 πœ‡π‘‹π‘ π‘¦ 2 {πœŽπ‘‹π‘ π‘¦ 2 + πœŽπ‘‰π‘ π‘¦ 2 }, 𝐸(πœ€π‘Œ 2) = 1 πœ‡π‘Œπ‘ π‘¦ 2 {πœŽπ‘Œπ‘ π‘¦ 2 + πœŽπ‘ˆπ‘ π‘¦ 2 }, 𝐸[πœ€π‘‹πœ€π‘Œ] = πœŒπœŽπ‘‹π‘ π‘¦πœŽπ‘Œπ‘ π‘¦ πœ‡π‘Œπ‘ π‘¦πœ‡π‘‹π‘ π‘¦ , 𝑅 = πœ‡π‘Œπ‘ π‘¦ πœ‡π‘‹π‘ π‘¦ , 𝐸(πœ€π‘‹ βˆ— πœ€π‘Œ βˆ—) = (πœŒπ‘Œπ‘‹πœŽπ‘‹π‘ π‘¦πœŽπ‘Œπ‘ π‘¦+πœŒπ‘ˆπ‘‰πœŽπ‘ˆπ‘ π‘¦πœŽπ‘‰π‘ π‘¦) πœ‡π‘Œπ‘ π‘¦πœ‡π‘‹π‘ π‘¦ , πœŽπ‘Œπ‘ π‘¦ 2 = 1 π‘˜ βˆ‘ (οΏ½Μ…οΏ½π‘˜π‘ π‘¦ π‘˜ 𝑖=1 βˆ’πœ‡π‘Œπ‘ π‘¦)2, πœŽπ‘‹π‘ π‘¦ 2 = 1 π‘˜ βˆ‘ (οΏ½Μ…οΏ½π‘˜π‘ π‘¦ π‘˜ 𝑖=1 βˆ’πœ‡π‘‹π‘ π‘¦)2, πœŽπ‘ˆπ‘ π‘¦ 2 = 1 π‘˜ βˆ‘ (�̅�𝑖.) 2π‘˜ 𝑖=1 , πœŽπ‘‰π‘ π‘¦ 2 = 1 π‘˜ βˆ‘ (�̅�𝑖.) 2π‘˜ 𝑖=1 , 2. Pre-Existing Estimators in the Presence of measurement error The mean estimator in the presence of measurement error is �̅�𝑠𝑦. The variance in the presence of measurement error is given as, 𝑉(οΏ½Μ…οΏ½π‘ π‘¦π‘š) = πœŽπ‘Œπ‘ π‘¦π‘š 2 = 1 π‘˜ βˆ‘ (�̅�𝑠𝑦 βˆ’ πœ‡π‘Œπ‘ π‘¦) 2π‘˜ 𝑖=1 = 1 π‘˜ βˆ‘ (�̅�𝑠𝑦 + �̅�𝑠𝑦 βˆ’ πœ‡π‘Œπ‘ π‘¦) 2π‘˜ 𝑖=1 (2.1) 𝑉(οΏ½Μ…οΏ½π‘ π‘¦π‘š) = πœŽπ‘Œπ‘ π‘¦ 2 + πœŽπ‘ˆπ‘ π‘¦ 2 (2.2) Ratio estimator in the presence of measurement error is defined as, οΏ½Μ…οΏ½π‘…π‘ π‘¦π‘š = �̅�𝑠𝑦 πœ‡π‘‹π‘ π‘¦ �̅�𝑠𝑦 (2.3) The mean square error of ratio estimator in the presence of measurement error is obtained as, π‘π‘–π‘Žπ‘ ( οΏ½Μ…οΏ½π‘…π‘ π‘¦π‘š) = 1 πœ‡π‘Œπ‘ π‘¦ {𝑅2(πœŽπ‘‹π‘ π‘¦ 2 + πœŽπ‘‰π‘ π‘¦ 2 ) βˆ’ πœŒπ‘…πœŽπ‘‹π‘ π‘¦πœŽπ‘Œπ‘ π‘¦} (2.4) Communications on Applied Nonlinear Analysis ISSN: 1074-133X Vol 32 No. 10s (2025) 1391 https://internationalpubls.com (οΏ½Μ…οΏ½π‘…π‘ π‘¦π‘š βˆ’ πœ‡π‘Œπ‘ π‘¦)2 = πœ‡π‘Œπ‘ π‘¦ 2 (πœ€π‘Œ 2 + πœ€π‘‹ 2 βˆ’ 2πœ€π‘Œπœ€π‘‹) (2.5) 𝑀𝑆𝐸(οΏ½Μ…οΏ½π‘…π‘ π‘¦π‘š) = [πœŽπ‘Œπ‘ π‘¦ 2 + πœŽπ‘ˆπ‘ π‘¦ 2 + 𝑅2(πœŽπ‘‹π‘ π‘¦ 2 + πœŽπ‘‰π‘ π‘¦ 2 ) βˆ’ 2πœŒπ‘…πœŽπ‘Œπ‘ π‘¦πœŽπ‘‹π‘ π‘¦]. (2.6) The bias in the presence of correlated measurement error is derived as, π‘π‘–π‘Žπ‘  (π‘¦βˆ—Μ…Μ… Μ… π‘…π‘ π‘¦π‘š ) = 1 πœ‡π‘Œπ‘ π‘¦ {𝑅2(πœŽπ‘‹π‘ π‘¦ 2 + πœŽπ‘‰π‘ π‘¦ 2 ) βˆ’ 𝑅(πœŒπœŽπ‘‹πœŽπ‘Œ + πœŒπ‘ˆπ‘‰πœŽπ‘ˆπœŽπ‘‰} (2.7) The mean square error in the presence of correlated measurement error is derived as 𝑀𝑆𝐸 (π‘¦βˆ—Μ…Μ… Μ… π‘…π‘ π‘¦π‘š ) = [πœŽπ‘Œπ‘ π‘¦ 2 + πœŽπ‘ˆπ‘ π‘¦ 2 + 𝑅2(πœŽπ‘‹π‘ π‘¦ 2 + πœŽπ‘‰π‘ π‘¦ 2 ) βˆ’ 2𝑅(πœŒπœŽπ‘‹π‘ π‘¦πœŽπ‘Œπ‘ π‘¦ + πœŒπ‘ˆπ‘‰πœŽπ‘ˆπ‘ π‘¦πœŽπ‘‰π‘ π‘¦)] (2.8) The product estimator in the presence of measurement error is οΏ½Μ…οΏ½π‘ƒπ‘ π‘¦π‘š = �̅�𝑠𝑦 �̅�𝑠𝑦 πœ‡π‘‹π‘ π‘¦ (2.9) The bias of the estimator is obtained as π‘π‘–π‘Žπ‘ (οΏ½Μ…οΏ½π‘ƒπ‘ π‘¦π‘š) = ( πœŒπœŽπ‘Œπ‘ π‘¦πœŽπ‘‹π‘ π‘¦ πœ‡π‘‹π‘ π‘¦ ) (2.10) The mean square error in the presence of uncorrelated measurement error is derived as 𝑀𝑆𝐸(οΏ½Μ…οΏ½π‘ƒπ‘ π‘¦π‘š) = (πœŽπ‘Œπ‘ π‘¦ 2 + πœŽπ‘ˆπ‘ π‘¦ 2 + 𝑅2(πœŽπ‘‹π‘ π‘¦ 2 + πœŽπ‘‰π‘ π‘¦ 2 ) + 2πœŒπ‘…πœŽπ‘Œπ‘ π‘¦πœŽπ‘‹π‘ π‘¦). (2.11) The mean square error in the presence of correlated measurement error is derived as 𝑀𝑆𝐸 (π‘¦βˆ—Μ…Μ… Μ… π‘ƒπ‘ π‘¦π‘š ) = (πœŽπ‘Œπ‘ π‘¦ 2 + πœŽπ‘ˆπ‘ π‘¦ 2 + 𝑅2(πœŽπ‘‹π‘ π‘¦ 2 + πœŽπ‘‰π‘ π‘¦ 2 ) + 2𝑅(πœŒπœŽπ‘‹π‘ π‘¦πœŽπ‘Œπ‘ π‘¦ + πœŒπ‘ˆπ‘‰πœŽπ‘ˆπ‘ π‘¦πœŽπ‘‰π‘ π‘¦). (2.12) The difference estimator in the presence of measurement error is οΏ½Μ…οΏ½π‘‘π‘ π‘¦π‘š = �̅�𝑠𝑦 + 𝑏(πœ‡π‘‹π‘ π‘¦ βˆ’ �̅�𝑠𝑦) (2.13) 𝑉(οΏ½Μ…οΏ½π‘‘π‘ π‘¦π‘š) = [(πœŽπ‘Œπ‘ π‘¦ 2 + πœŽπ‘ˆπ‘ π‘¦ 2 ) + 𝑏2(πœŽπ‘‹π‘ π‘¦ 2 + πœŽπ‘‰π‘ π‘¦ 2 ) βˆ’ 2π‘πœŒπœŽπ‘Œπ‘ π‘¦πœŽπ‘‹π‘ π‘¦]. (2.14) After differentiating the above equation we get, 𝑑(𝑉(οΏ½Μ…οΏ½π‘‘π‘ π‘¦π‘š)) 𝑑𝑏 = [2𝑏(πœŽπ‘‹π‘ π‘¦ 2 + πœŽπ‘‰π‘ π‘¦ 2 ) βˆ’ 2πœŒπœŽπ‘Œπ‘ π‘¦πœŽπ‘‹π‘ π‘¦] (2.15) Equating the above equation to zero gives, 𝑏 = πœŒπœŽπ‘Œπ‘ π‘¦πœŽπ‘‹π‘ π‘¦ (πœŽπ‘‹π‘ π‘¦ 2 +πœŽπ‘‰π‘ π‘¦ 2 ) (2.16) Now substituting the value of 𝑏, the minimum variance is obtained as 𝑉(οΏ½Μ…οΏ½π‘‘π‘ π‘¦π‘š) = [(πœŽπ‘Œπ‘ π‘¦ 2 + πœŽπ‘ˆπ‘ π‘¦ 2 ) βˆ’ 𝜌2πœŽπ‘Œπ‘ π‘¦ 2 πœŽπ‘‹π‘ π‘¦ 2 (πœŽπ‘‹π‘ π‘¦ 2 +πœŽπ‘Œπ‘ π‘¦ 2 ) ] (2.17) Communications on Applied Nonlinear Analysis ISSN: 1074-133X Vol 32 No. 10s (2025) 1392 https://internationalpubls.com 3. 1. Proposed Class of Estimators The proposed class of estimators in the presence of measurement error is οΏ½Μ‚οΏ½π‘Œπ‘…πΈπ‘ π‘¦π‘š = �̅�𝑠𝑦𝑒π‘₯𝑝 ( πœ‡π‘‹π‘ π‘¦π‘š βˆ’οΏ½Μ…οΏ½π‘ π‘¦ πœ‡π‘‹π‘ π‘¦π‘š+�̅�𝑠𝑦+2𝐾 ) (3.1.1) 𝑀𝑆𝐸(οΏ½Μ‚οΏ½π‘Œπ‘…π‘ π‘¦π‘š) = [(πœŽπ‘Œπ‘ π‘¦ 2 + πœŽπ‘ˆπ‘ π‘¦ 2 ) + (πœŽπ‘Œπ‘ π‘¦ 2 +πœŽπ‘ˆπ‘ π‘¦ 2 ) 4(πœ‡π‘‹π‘ π‘¦π‘š+𝐾2) βˆ’ 𝜌2πœŽπ‘Œπ‘ π‘¦ 2 πœŽπ‘‹π‘ π‘¦ 2 (πœ‡π‘‹π‘ π‘¦π‘š+𝐾2)(πœŽπ‘‹π‘ π‘¦ 2 +πœŽπ‘‰π‘ π‘¦ 2 ) ] (3.1.2) In order to obtain the min. MSE differentiate (3.1.2) w.r.t 𝐾 and equate it to zero 𝑑 𝑑𝐾 (πœ‡ Μ‚ π‘Œπ‘…πΈπ‘ π‘¦π‘š) = 0 (3.1.3) 𝐾 = βˆ’πœ‡π‘‹π‘ π‘¦π‘š + πœ‡π‘Œπ‘ π‘¦ 2 βˆ’ (πœŽπ‘Œπ‘ π‘¦ 2 + πœŽπ‘ˆπ‘ π‘¦ 2 )/𝑆π‘₯𝑦 (3.1.4) After substituting the value of 𝐾 mean square error of the estimators we can write from equation (3.1.2) as π‘šπ‘–π‘›. 𝑀𝑆𝐸(οΏ½Μ‚οΏ½π‘Œπ‘ π‘¦π‘š) = (πœŽπ‘Œπ‘ π‘¦ 2 + πœŽπ‘ˆπ‘ π‘¦ 2 ) βˆ’ 𝜌2πœŽπ‘Œπ‘ π‘¦ 2 πœŽπ‘‹π‘ π‘¦ 2 (πœŽπ‘‹π‘ π‘¦ 2 +πœŽπ‘‰π‘ π‘¦ 2 ) (3.1.5) 3.2. Bias and Mean Square Error for the correlated measurement error The minimum mean square error of the proposed class of estimator in the presence of correlated measurement error is obtained as 𝑀𝑆𝐸(οΏ½Μ‚οΏ½π‘Œπ‘ π‘¦π‘š) = (πœŽπ‘Œπ‘ π‘¦ 2 + πœŽπ‘ˆπ‘ π‘¦ 2 ) βˆ’ (πœŒπœŽπ‘‹π‘ π‘¦πœŽπ‘Œπ‘ π‘¦+πœŒπ‘ˆπ‘‰πœŽπ‘‰π‘ π‘¦πœŽπ‘ˆπ‘ π‘¦) 2 (πœŽπ‘‹π‘ π‘¦ 2 +πœŽπ‘‰π‘ π‘¦ 2 ) (3.2.1) 5.1. Simulation Study In order to show the efficiency of the estimators and to show the impact of uncorrelated and correlated measurement error on the mse simulation study is conducted by using R studio. A data matrix is generated using multivariate normal distribution on the auxiliary variable 𝑋, study variable π‘Œ and the error variables π‘ˆ and 𝑉 and the four variables 𝑋, π‘Œ, π‘ˆ and 𝑉 are with mean (πœ‡π‘‹π‘ π‘¦, πœ‡π‘Œπ‘ π‘¦, 0,0). The covariance matrix is: ( π‘†π‘Œ 2 πœŒπ‘†π‘‹π‘†π‘Œ 0 0 πœŒπ‘†π‘‹π‘†π‘Œ 𝑆𝑋 2 0 0 0 0 π‘†π‘ˆ 2 πœŒπ‘ˆπ‘‰π‘†π‘ˆπ‘†π‘‰ 0 0 πœŒπ‘ˆπ‘‰π‘†π‘ˆπ‘†π‘‰ 𝑆𝑉 2 ) Here π‘†π‘Œ 2 and 𝑆𝑋 2 is the standard deviation of the study variable π‘Œ and 𝑋.. Communications on Applied Nonlinear Analysis ISSN: 1074-133X Vol 32 No. 10s (2025) 1393 https://internationalpubls.com π‘†π‘ˆ 2 and 𝑆𝑉 2 is the standard deviation of the measurement error π‘ˆ associated with study variable π‘Œ sample and 𝑉 is associated with the auxiliary variable 𝑋. 𝜌 is the correlation coefficient between the study variable π‘Œ and auxiliary variable 𝑋. πœŒπ‘ˆπ‘‰ is the correlation coefficient between the measurement errors of π‘ˆ and 𝑉 the study variable π‘Œ and auxiliary variable 𝑋. From the simulation by using R studio , data is generated for multivariate normal distribution with mean vector for (πœ‡π‘‹π‘ π‘¦, πœ‡π‘Œπ‘ π‘¦, 0, 0) = (50,60,0,0) and 𝑆𝑋 = 35, π‘†π‘Œ = 25. From the generated data 10, systematic samples has been taken. The statistics is calculated for the generated data set. The Mean square error is defined as the expectation of the squared difference between the value that is estimated and true value. The mean squared error for the proposed class of estimators is obtained and compared with the mean square error for the ratio and product estimator for different combinations of πœŒπ‘‹π‘Œ = (0.95, 0.55, βˆ’0.95, βˆ’0.55) and πœŒπ‘ˆπ‘‰ = (0.95, 0.55, 0.0, βˆ’0.95, βˆ’0.55). To illustrate the performance of the estimator under measurement error and correlated measurement error 6 tables is created. Table 1: MSE and PRE of various estimators of ππ’€π’”π’š for 𝝆𝑼𝑽 = (𝟎. πŸ—πŸ“, 𝟎. πŸ“πŸ“, 𝟎. 𝟎, βˆ’πŸŽ. πŸ—πŸ“, βˆ’πŸŽ. πŸ“πŸ“) and 𝝆𝑿𝒀 = (𝟎. πŸ—πŸ“, 𝟎. πŸ“πŸ“, βˆ’πŸŽ. πŸ—πŸ“, βˆ’πŸŽ. πŸ“πŸ“) when (πˆπ‘Ό 𝟐 , πˆπ‘½ 𝟐) = (𝟎, 𝟎) and (πˆπ’€ 𝟐 , πˆπ‘Ώ 𝟐 ) = (πŸπŸ“, 𝟐𝟎) and 𝑡 = 𝟏𝟎𝟎𝟎 and 𝒏 = 𝟏𝟎. ΟƒU 2 ΟƒV 2 ρXY ρUV MSE var (ΞΌΜ‚sym) ΞΌΜ‚Rsym ΞΌΜ‚Psym yΜ…sym 0 0 .95 0.95 0.55 0.0 -.95 -.55 0.791 0.705 0.703 1.908 0.742 1.038 0.844 0.836 2.405 1.143 24.263 31.948 23.633 61.18 35.259 8.187 7.74 7.313 19.565 7.611 .55 0.95 0.55 0.0 -.95 - 6.82 10.63 16.29 12.82 13.32 11.467 18.439 16.449 14.865 19.251 38.284 60.889 48.846 50.588 65.774 9.964 15.25 23.367 18.387 19.1 Communications on Applied Nonlinear Analysis ISSN: 1074-133X Vol 32 No. 10s (2025) 1394 https://internationalpubls.com Table 2: MSE and PRE of various estimators of ππ’€π’”π’š for 𝝆𝑼𝑽 (𝟎. πŸ—πŸ“, 𝟎. πŸ“πŸ“, 𝟎. 𝟎, βˆ’πŸŽ, πŸ—πŸ“, βˆ’πŸŽ. πŸ“πŸ“) and 𝝆𝑿𝒀 = (𝟎. πŸ—πŸ“, 𝟎. πŸ“πŸ“, βˆ’πŸŽ. πŸ—πŸ“, βˆ’πŸŽ. πŸ“πŸ“) when (πˆπ‘Ό 𝟐 , πˆπ‘½ 𝟐) = (𝟐, 𝟐) and (πˆπ’€ 𝟐 , πˆπ‘Ώ 𝟐 ) = (πŸπŸ“, 𝟐𝟎) and 𝑡 = 𝟏𝟎𝟎𝟎 and 𝒏 = 𝟏𝟎. ΟƒU 2 ΟƒV 2 ρXY ρUV MSE Var ΞΌΜ‚sym ΞΌΜ‚Rsym ΞΌΜ‚Psym yΜ…sym 2 2 0.95 .95 .55 0.0 -.95 -.55 2.965 3.092 4.693 6.66 4.039 3.036 3.544 4.913 7.346 4.313 107.252 66.777 75.321 62.727 35.695 30.411 21.80 24.37 17.74 10.54 0.55 0.95 0.55 0.0 -.95 11.651 11.436 10.895 9.606 8.599 11.707 12.912 12.726 15.486 15.453 38.672 43.573 35.056 35.752 40.151 17.807 16.396 14.067 11.413 10.847 0.55 -.95 0.95 0.55 0.0 -.95 -.55 0.791 1.688 1.08 1.473 1.417 32.482 62.741 40.936 55.217 49.023 0.838 1.697 1.081 1.475 1.534 8.112 17.315 11.081 15.103 14.53 -.55 0.95 0.55 0.0 -.95 -.55 11.02 5.724 15.76 7.554 5.466 34.034 20.841 66.635 32.194 31.118 11.203 6.267 19.386 9.36 9.408 15.803 8.206 22.607 10.83 7.837 Communications on Applied Nonlinear Analysis ISSN: 1074-133X Vol 32 No. 10s (2025) 1395 https://internationalpubls.com -.55 -.95 0.95 0.55 0.0 -.95 -.55 6.633 4.687 3.442 2.591 2.243 53.846 56.463 53.616 90.902 44.812 6.648 5.388 3.56 2.686 2.247 18.864 14.792 14.799 26.138 13.082 -.55 0.95 0.55 0.0 -.95 -.55 16.095 13.339 15.91 7.796 17.332 61.465 58.549 84.222 45.465 88.096 22.308 20.043 27.213 12.467 25.926 20.596 17.613 21.92 11.749 24.841 Table 3: MSE and PRE of various estimators of ππ’€π’”π’š for 𝝆𝑼𝑽 = (𝟎. πŸ—πŸ“, 𝟎. πŸ“πŸ“, 𝟎. 𝟎, βˆ’πŸŽ, πŸ—πŸ“, βˆ’πŸŽ. πŸ“πŸ“) and 𝝆𝑿𝒀 = (𝟎. πŸ—πŸ“, 𝟎. πŸ“πŸ“, βˆ’πŸŽ. πŸ—πŸ“, βˆ’πŸŽ. πŸ“πŸ“) when (πˆπ‘Ό 𝟐 , πˆπ‘½ 𝟐) = (πŸ’, πŸ’) and (πˆπ’€ 𝟐 , πˆπ‘Ώ 𝟐 ) = (πŸπŸ“, 𝟐𝟎) and 𝑡 = 𝟏𝟎𝟎𝟎 and 𝒏 = 𝟏𝟎 ΟƒU 2 ΟƒV 2 ρXY ρUV MSE var ΞΌΜ‚sym ΞΌΜ‚Rsym ΞΌΜ‚Psym yΜ…sym 4 4 0.95 0.95 0.55 0.0 -.95 -.55 2.353 4.445 7.395 7.514 8.056 2.643 4.465 8.427 8.225 10.334 77.652 61.691 33.187 56.347 22.252 23.588 19.296 11.521 16.952 9.331 0.55 0.95 0.55 0.0 -.95 -.55 22.598 10.359 19.769 19.429 22.739 26.067 12.593 19.964 28.441 33.259 94.832 42.14 45.97 48.519 62.502 33.61 14.65 25.237 20.859 25.083 -.95 0.95 0.55 17.371 16.009 11.014 62.62 65.209 63.253 20.624 18.873 11.674 23.431 23.091 21.304 Communications on Applied Nonlinear Analysis ISSN: 1074-133X Vol 32 No. 10s (2025) 1396 https://internationalpubls.com 0.0 -.95 -.55 1.594 3.777 56.864 42.463 1.644 3.934 16.255 12.257 -.55 0.95 0.55 0.0 -.95 -.55 20.826 15.327 8.238 8.888 12.416 53.655 39.353 36.754 53.181 60.757 30.339 30.452 15.683 11.712 18.679 22.576 15.583 9.943 15.076 17.367 Table 4: MSE and PRE of various estimators of ππ’€π’”π’š for 𝝆𝑼𝑽 = (𝟎. πŸ—πŸ“, 𝟎. πŸ“πŸ“, 𝟎. 𝟎, βˆ’πŸŽ, πŸ—πŸ“, βˆ’πŸŽ. πŸ“πŸ“) and𝝆𝑿𝒀 = (𝟎. πŸ—πŸ“, 𝟎. πŸ“πŸ“, βˆ’πŸŽ. πŸ—πŸ“, βˆ’πŸŽ. πŸ“πŸ“) when (πˆπ‘Ό 𝟐 , πˆπ‘½ 𝟐) = (𝟎, 𝟎) and (πˆπ’€ 𝟐 , πˆπ‘Ώ 𝟐 ) = (πŸπŸ“, πŸ‘πŸ“) and 𝑡 = 𝟏𝟎𝟎𝟎 and 𝒏 = 𝟏𝟎. ΟƒU 2 ΟƒV 2 ρXY ρUV MSE var ΞΌΜ‚sym ΞΌΜ‚Rsym ΞΌΜ‚Psym yΜ…sym 0 0 .95 .95 .55 0.0 -.95 -.55 1.99 1.14 3.206 2.117 1.752 2.105 1.187 3.393 2.202 1.904 81.594 46.199 131.50 85.741 73.051 20.40 11.69 32.87 21.71 17.96 0.55 .95 .55 0.0 -.95 -.55 14.18 15.74 18.69 77.203 24.151 17.988 19.387 18.115 10.442 36.072 61.942 66.648 57.044 35.662 122.664 20.34 22.56 12.46 34.625 - 0.95 .95 .55 0.0 -.95 4.102 2.013 1.27 1.607 4.866 143.92 671.11 453.32 863.693 4.352 2.115 1.398 1.634 4.889 42.07 20.64 13.02 16.47 Communications on Applied Nonlinear Analysis ISSN: 1074-133X Vol 32 No. 10s (2025) 1397 https://internationalpubls.com -.55 189.115 49.90 -.55 .95 .55 0.0 -.95 -.55 8.069 14.068 7.148 24.73 8.322 37.133 52.502 51.253 107.91 644.93 10.791 15.654 16.881 31.339 13.389 11.56 20.16 10.24 35.45 11.93 Table 5: MSE and PRE of various estimators of ππ’€π’”π’š for 𝝆𝑼𝑽 = (𝟎. πŸ—πŸ“, 𝟎. πŸ“πŸ“, 𝟎. 𝟎, βˆ’πŸŽ, πŸ—πŸ“, βˆ’πŸŽ. πŸ“πŸ“) and 𝝆𝑿𝒀 = (𝟎. πŸ—πŸ“, 𝟎. πŸ“πŸ“, βˆ’πŸŽ. πŸ—πŸ“, βˆ’πŸŽ. πŸ“πŸ“) when (πˆπ‘Ό 𝟐 , πˆπ‘½ 𝟐) = (𝟐, 𝟐) and (πˆπ’€ 𝟐 , πˆπ‘Ώ 𝟐 ) = (πŸπŸ“, πŸ‘πŸ“) and 𝑡 = 𝟏𝟎𝟎𝟎 and 𝒏 = 𝟏𝟎. ΟƒU 2 ΟƒV 2 ρXY ρUV MSE var ΞΌΜ‚sym ΞΌΜ‚Rsym ΞΌΜ‚Psym yΜ…sym 2 2 0.95 0.95 0.55 0.0 -.95 -.55 1.987 4.224 6.209 8.832 5.389 2.298 4.474 6.763 8.997 7.071 85.301 78.166 121.738 127.646 108.037 20.348 24.923 31.228 40.796 24.903 0.55 0.95 0.55 0.0 -.95 -.55 6.515 12.925 5.413 13.497 23.983 12.478 14.524 11.423 33.11 26.047 44.475 48.501 33.232 80.573 54.299 9.974 18.447 7.405 17.034 28.124 -.95 0.95 0.55 0.0 -.95 -.55 10.439 7.815 6.019 2.819 5.886 85.623 144.45 103.521 119.038 160.013 10.506 8.982 6.103 3.808 5.886 30.379 35.953 28.986 26.76 44.336 Communications on Applied Nonlinear Analysis ISSN: 1074-133X Vol 32 No. 10s (2025) 1398 https://internationalpubls.com -.55 0.95 0.55 0.0 -.95 -.55 12.365 22.751 13.301 18.897 22.275 40.978 84.452 53.519 82.443 74.537 21.946 27.465 17.381 22.246 23.301 13.634 30.828 17.971 28.326 31.935 Table 6: MSE and PRE of various estimators of ππ’€π’”π’š for 𝝆𝑼𝑽 = (𝟎. πŸ—πŸ“, 𝟎. πŸ“πŸ“, 𝟎. 𝟎, βˆ’πŸŽ, πŸ—πŸ“, βˆ’πŸŽ. πŸ“πŸ“) and 𝝆𝑿𝒀 = (𝟎. πŸ—πŸ“, 𝟎. πŸ“πŸ“, βˆ’πŸŽ. πŸ—πŸ“, βˆ’πŸŽ. πŸ“πŸ“) when (πˆπ‘Ό 𝟐 , πˆπ‘½ 𝟐) = (πŸ’, πŸ’) and (πˆπ’€ 𝟐 , πˆπ‘Ώ 𝟐 ) = (πŸπŸ“, πŸ‘πŸ“) and 𝑡 = 𝟏𝟎𝟎𝟎 and 𝒏 = 𝟏𝟎. ΟƒU 2 ΟƒV 2 ρXY ρUV MSE var ΞΌΜ‚sym ΞΌΜ‚Rsym ΞΌΜ‚Psym yΜ…sym 4 4 0.95 0.95 0.55 0.0 -.95 -.55 2.179 2.738 14.226 14.163 13.767 2.191 3.255 15.702 17.719 15.059 79.529 48.267 153.798 55.637 61.066 21.996 11.824 42.31 19.349 22.006 0.55 0.95 0.55 0.0 -.95 -.55 23.383 20.011 26.354 31.146 14.102 34.379 24.771 32.019 40.656 22.02 130.356 84.505 92.99 83.963 48.613 35.727 28.564 34.714 35.522 16.444 -0.95 0.95 0.55 0.0 -.95 -.55 15.811 11.338 5.359 2.522 4.189 58.113 79.016 74.701 82.203 101.412 18.213 12.265 6.132 3.128 4.311 21.947 24.529 19.226 19.12 26.803 -0.55 0.95 0.55 0.0 -.95 -.55 17.646 14.695 17.007 19.215 8.308 62.357 70.549 70.806 113.737 54.996 39.282 28.031 22.684 29.443 19.39 18.682 18.347 23.137 29.856 11.378 Communications on Applied Nonlinear Analysis ISSN: 1074-133X Vol 32 No. 10s (2025) 1399 https://internationalpubls.com Results from the tables: From the table 1 for πœŒπ‘‹π‘Œ = 0.95 and πœŒπ‘ˆπ‘‰ = (0.95, 0.55, 0.0, βˆ’0.95, βˆ’0.55) as the correlation between the study variable π‘Œ and auxiliary variable 𝑋 is positively correlated the ratio estimator performs well. As observed from the table when πœŒπ‘‹π‘Œ = 0.95 the mse of the ratio estimator is very less as compared to the mse of product estimator but the mean square error for the proposed class of estimators is less than that of the ratio estimator. From the table 1, for πœŒπ‘‹π‘Œ = 0.55 and πœŒπ‘ˆπ‘‰ = (0.95, 0.55, 0.0, βˆ’0.95, βˆ’0.55) as the correlation between the study variable π‘Œ and auxiliary variable 𝑋 is positively correlated the ratio estimator performs well. As observed from the table when πœŒπ‘‹π‘Œ = 0.55 the mse of the ratio estimator is very less as compared to the product estimator but the mse for the proposed class of estimators is less than that of the ratio estimator. From the table 1 for πœŒπ‘‹π‘Œ = βˆ’0.95 and πœŒπ‘ˆπ‘‰ = (0.95, 0.55, 0.0, βˆ’0.95, βˆ’0.55) as the correlation between the study variable π‘Œ and auxiliary variable 𝑋 is negatively correlated the product estimator performs well. As observed from the table when πœŒπ‘‹π‘Œ = βˆ’0.95 the mean square error of the product estimator is very less as compared to mse of the ratio estimator but the mse for the proposed class of estimators is less than that of the product estimator. From the table 1 for πœŒπ‘‹π‘Œ = βˆ’0.55 and πœŒπ‘ˆπ‘‰ = (0.95, 0.55, 0.0, βˆ’0.95, βˆ’0.55) as the correlation between the study variable π‘Œ and auxiliary variable 𝑋 is negatively correlated the product estimator performs well. As observed from the table when πœŒπ‘‹π‘Œ = βˆ’0.55 the mse of the product estimator is very less as compared to the mean square error of ratio estimator but the mean square error for the proposed class of estimators is less than that of the product estimator. The above results are observed when auxiliary variable 𝑋, study variable π‘Œ and the error variables π‘ˆ and 𝑉 are with mean (πœ‡π‘‹π‘ π‘¦, πœ‡π‘Œπ‘ π‘¦, 0, 0) and the population variance of the study variable and auxiliary variable 𝑋, π‘Œare (15, 20) and the variance of the measurement errors π‘ˆ and 𝑉 are taken as (0,0), (2,2) and (4,4). A similar pattern is observed as described above is followed when the population variance of the study variable and auxiliary variable 𝑋, π‘Œ are increased to (25,35) and for the same values of variance of the measurement errors π‘ˆ and 𝑉. Conclusions In this manuscript, the effect of measurement error and correlated measurement error on the exponential estimator, under systematic sampling technique to estimate the population mean of the study variable π‘Œ by using the auxiliary information has been studied. The observation is assumed to be recorded with some errors. Also, the error present in study and auxiliary variable are assumed to be correlated. From the simulation study, it is observed that proposed method of estimation is more efficient than ratio and product and mean estimator . From simulation study, it is concluded that the mse in the presence of measurement error as well as in the presence of correlated measurement error is always high. Due to simplicity, systematic sampling has wide applicability and thus, the proposed method of estimation can be applied to many real-life events under systematic sampling survey where the data are prone to recorded with measurement error and as well as correlated measurement error. The limitation of the study is that the method of estimation is derived for systematic sampling. Communications on Applied Nonlinear Analysis ISSN: 1074-133X Vol 32 No. 10s (2025) 1400 https://internationalpubls.com References: [1] Cochran, W. G. (1946). 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