Search

In the statistical literature, truncated distributions can be used for modeling real data. Due to error of measurement in truncated continuous data, choosing a crisp trimmed point caucuses a fault inference, so using fuzzy sets to define a threshold pointmay leads us more efficient results with respect to crisp thresholds. Arellano-Valle et al. [2] defined a selection distribution for analysis of truncated data with crisp threshold. In this paper, we define fuzzy multivariate selection distribution that is an extension of the selection distributions using fuzzy threshold. A practical data set with a fuzzy threshold point is considered to investigate the relationship between high blood pressure and BMI.

An approach is proposed to construct fuzzy confidence intervals for unknown parameters in statistical models. In this approach, a family of confidence intervals of the unknown crisp parameters is considered. Such confidence intervals are used to obtain a fuzzy confidence interval for the parameter of interest. The proposed approach enjoys a wide range of confidence intervals to obtain a trapezoidal shaped fuzzy set of the parameter space as the fuzzy confidence interval for the parameter of interest. By using the resolution identity, it is shown that the constructed fuzzy confidence intervals are really fuzzy sets of the parameter space. Some numerical examples are provided to explain the functionality of the approach at one-sided and two-sided fuzzy confidence intervals. Moreover, the application of this proposed approach in health sciences is provided for the case of the recovery time of olfactory and gustatory dysfunctions for COVID-19 patients. [ABSTRACT FROM AUTHOR]

In order to monitor the mean and variability of a process, the Gini control charts are proposed based on the skew normally distributed random sample. By comparing the false alarm rates of current scheme with those of existing mean and dispersion control charts, it was found that the design structure of Gini chart could be enhanced in comparison to other classic schemes based on the assumption of skew normal distribution for the data. Moreover, the superiority of the Gini chart was investigated by comparing the discriminatory power curves of the skew normal distribution with some existing control charts. Simulated studies and a real data example illustrate the usefulness of the proposed approach. [ABSTRACT FROM AUTHOR]

TIn this work we carry out a multiple imputation technique for handling missing observations. We propose an algorithm, which performs a hierarchical multiple imputation using edition rules to impute missing values. We assess our algorithm using a simulation study and a numerical application of our algorithm in dataset of Kerman Chamber of Commerce, Industries, Mines and Agriculture is presented for more illustration. [ABSTRACT FROM AUTHOR]

Abstract: The hesitant fuzzy sets are a new efficient mathematical approach to study imprecise, uncertain, or incomplete knowledge. This paper focuses to extend this approach on a lattice and shows that two large application concepts of the fuzzy set theory namely resolution identity and representation theorem are true under this extended definition. [ABSTRACT FROM AUTHOR]

Fuzzy relation inequalities based on max-F composition are dis- cussed, where F is a binary aggregation on [0,1]. For a fixed fuzzy relation inequalities system A' 0Fx ≤b, we characterize all matrices A' For which the solution set of the system A' 0 F x ≤b is the same as the original solution set. Similarly, for a fixed matrix A, the possible perturbations b 0 of the right-hand side vector b not modifying the original solution set are determined. Several illustrative examples are included to clarify the results of the paper. [ABSTRACT FROM AUTHOR]