An Improved Textbook Rule on the Mean-Median Inequality for Discrete Data

2020-04-01
Objective: Many introductory statistics books cover the mean-median inequality, which states that if the skewness value is positive/negative, the mean is greater/less than the median. However, this textbook rule is often violated especially when one tail is long and the other is heavy. The purpose of this paper is to propose a refinement that solves the problem to a meaningful extent by bringing the area to the left and right of the median into the picture for discrete data, where violations are more common and severe. The improved version is simple and effective enough to replace the existing rule. Material and Methods: Three distributional settings were utilized for illustration: The Poisson, binomial, and discretized normal mixture distributions. A simulation study was devised to assess the relative performances of the current and new rules for count data under the Poisson distribution assumption. Results: The new rule adds a simple layer to the current rule: For right skew, the mean is greater/less than the median if the area to the left of the median is less/greater than the area to the right. Similarly, for left skew, the mean is less/greater than the median if the area to the left the median is greater/less than the area to the right. In other words, the new component comes in the form of a comparative area restriction. Conclusion: All three distributional examples lead to the same Conclusion: The proposed version is associated with substantially better results. Although it is not a complete solution, it is a serious improvement.
Türkiye Klinikleri Biyoistatistik Dergisi

Suggestions

A decomposition approach for undiscounted two-person zero-sum stochastic games
Avşar, Zeynep Müge (Springer Science and Business Media LLC, 1999-06-01)
Two-person zero-sum stochastic games are considered under the long-run average expected payoff criterion. State and action spaces are assumed finite. By making use of the concept of maximal communicating classes, the following decomposition algorithm is introduced for solving two-person zero-sum stochastic games: First, the state space is decomposed into maximal communicating classes. Then, these classes are organized in an hierarchical order where each level may contain more than one maximal communicating ...
An exact algorithm for the minimum squared load assignment problem
Karsu, Özlem; Azizoğlu, Meral (Elsevier BV, 2019-06)
In this study, we consider an assignment problem with the objective to minimize the sum of squared loads over all agents. We provide mixed integer nonlinear and linear programming formulations of the problem and present a branch and bound algorithm for their solution. The results of our computational experiment have shown the satisfactory behavior of our branch and bound algorithm.
Estimation and hypothesis testing in multivariate linear regression models under non normality
İslam, Muhammed Qamarul (Informa UK Limited, 2017-01-01)
This paper discusses the problem of statistical inference in multivariate linear regression models when the errors involved are non normally distributed. We consider multivariate t-distribution, a fat-tailed distribution, for the errors as alternative to normal distribution. Such non normality is commonly observed in working with many data sets, e.g., financial data that are usually having excess kurtosis. This distribution has a number of applications in many other areas of research as well. We use modifie...
An Approach for determining process economy parameters of multivariate loss functions
Özkan, Gökçe; Köksal, Gülser; Department of Industrial Engineering (2016)
The aim of this study is to provide an effective method for determining parameters of multivariate loss functions, which are related with process economics. The loss functions are widely used in product and process design and other quality engineering applications. Although there are several studies about different types of loss functions, there is a lack of studies on determining cost matrix parameters of these functions. For this purpose, we propose a method based on multi-objective decision making tools....
An error analysis of iterated defect correction methods for linear differential-algebraic equations
Karasözen, Bülent (1996-01-01)
Asymptotic expansions of the global error of iterated defect correction (IDeC) techniques based on the implicit Euler method for linear differential-algebraic equations (dae's) of arbitrary index are analyzed. The dependence of the maximum attainable convergence order on the degree of the interpolating polynomial, number of defect correction steps, and on the index of the differential-algebraic system is given. The efficiency of IDeC method and extrapolation is compared on the basis of numerical experiments...
Citation Formats
C. Vardar Acar, “An Improved Textbook Rule on the Mean-Median Inequality for Discrete Data,” Türkiye Klinikleri Biyoistatistik Dergisi, pp. 158–167, 2020, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/35513.