Multicriteria Decision-Making Under High-Level Uncertainty In Tourism: Z-Numbers Based Approaches

The objective of this paper is to study the applicability and effectiveness of the decision-making models in the tourism sector under high-level uncertainty, formalized by Z-information. The topicality of this issue is significantly increased after the outbreak of the pandemic. Fuzzy multi-criteria decision-making (MCDM) models applied in the tourism area are partially solving this problem. But in these models, researchers are not paying due attention to the reliability of the information. One approach available for the formalization of such high-level uncertainty is the use of bi-component Z-number = (A, B). Components of the Z-numbers are expressed by perception-based fuzzy numbers. Part A defines the value of the uncertain variable and part B defines the confidence in this value. This approach allows considering the fuzzy-probabilistic nature of the information used for decision-making in tourism. In the paper, we are describing in detail the Z-numbers-based approach for the tourism destination selection task solution under high-level uncertainty. The model has been developed for the water sports tourism destination selection in Turkey. Initial information for model construction was derived via surveys. For the solution of this task, the Z-TOPSIS method is used. Results of the task solution illustrate the efficiency of the Z-numbers-based model for destination selection and the applicability of the approach for other MCDM tasks in tourism

Selection Of The Hotel Suppliers Under High-Level Uncertainty

The objective of this paper is to develop a model for supplier selection under high-level uncertainty in the decision-making environment. The pandemic seriously affected the economic well-being of the hospitality industry, decreased travel and tourists` numbers, undermined hospitality service delivery systems and their financial stability. Business structures and relationships, developed in the industry during several decades of stability, have been destroyed fully or partially, and service quality is deteriorating. One of the consequences of the pandemic is supply chains disruptions, caused by the inabilities of suppliers to provide services according to customer requirements. Given that, it is necessary to solve the problem of supplier selection for the tourism sector taking into consideration specifics of the pandemic and post-pandemic conditions. During pandemic and post-pandemic recovery, internal and external environments of the business tasks are characterized by the high-level of uncertainty, insufficiency, and subjectivity of the available information. Supply chain management task is a classic example of such tasks, and it is necessary to develop an approach that can operate with uncertainties and subjectivity of various nature, inherent to this decision-making problem. In such circumstances, traditional probabilistic or fuzzy methods may not always be relevant for formalizing uncertainties, and the use of perception-based dual-natured (fuzzy & probabilistic) Z-numbers may be more appropriate. Z-number-based multi-criteria decision-making (MCDM) method ZVIKOR was used to select alternatives (suppliers) for the hotels. The criteria for the supplier selection were determined by Delphi analysis. The supplier selection task is solved on the example of hotels in Turkey and Azerbaijan. Results of the research illustrate the applicability of the approach for solving MCDM problems in the tourism sector under conditions of highlevel uncertainty

Z-Numbers-Based Approach to Hotel Service Quality Assessment

In this study, we are analyzing the possibility of using Z-numbers for measuring the service quality and decision-making for quality improvement in the hotel industry. Techniques used for these purposes are based on consumer evalu- ations - expectations and perceptions. As a rule, these evaluations are expressed in crisp numbers (Likert scale) or fuzzy estimates. However, descriptions of the respondent opinions based on crisp or fuzzy numbers formalism not in all cases are relevant. The existing methods do not take into account the degree of con- fidence of respondents in their assessments. A fuzzy approach better describes the uncertainties associated with human perceptions and expectations. Linguis- tic values are more acceptable than crisp numbers. To consider the subjective natures of both service quality estimates and confidence degree in them, the two- component Z-numbers Z = (A, B) were used. Z-numbers express more adequately the opinion of consumers. The proposed and computationally efficient approach (Z-SERVQUAL, Z-IPA) allows to determine the quality of services and iden- tify the factors that required improvement and the areas for further development. The suggested method was applied to evaluate the service quality in small and medium-sized hotels in Turkey and Azerbaijan, illustrated by the example

Acute Acalculous Cholecystitis due to Viral Hepatitis A

Inflammation of the gallbladder without evidence of calculi is known as acute acalculous cholecystitis (AAC). AAC is frequently associated with gangrene, perforation, and empyema. Due to these associated complications, AAC can be associated with high morbidity and mortality. Medical or surgical treatments can be chosen according to the general condition of the patient, underlying disease and agent. Particularly in acute acalculous cholecystitis cases, early diagnosis and early medical treatment have a positive effect on the patient and protect them from surgical trauma. ACC is a rare complication of acute viral hepatitis A. Herein, we present an adult patient of acalculous cholecystitis due to acute viral hepatitis A. She responded to the conservative management

Clinical and molecular evaluation of MEFV gene variants in the Turkish population: a study by the National Genetics Consortium

Familial Mediterranean fever (FMF) is a monogenic autoinflammatory disorder with recurrent fever, abdominal pain, serositis, articular manifestations, erysipelas-like erythema, and renal complications as its main features. Caused by the mutations in the MEditerranean FeVer (MEFV) gene, it mainly affects people of Mediterranean descent with a higher incidence in the Turkish, Jewish, Arabic, and Armenian populations. As our understanding of FMF improves, it becomes clearer that we are facing with a more complex picture of FMF with respect to its pathogenesis, penetrance, variant type (gain-of-function vs. loss-of-function), and inheritance. In this study, MEFV gene analysis results and clinical findings of 27,504 patients from 35 universities and institutions in Turkey and Northern Cyprus are combined in an effort to provide a better insight into the genotype-phenotype correlation and how a specific variant contributes to certain clinical findings in FMF patients. Our results may help better understand this complex disease and how the genotype may sometimes contribute to phenotype. Unlike many studies in the literature, our study investigated a broader symptomatic spectrum and the relationship between the genotype and phenotype data. In this sense, we aimed to guide all clinicians and academicians who work in this field to better establish a comprehensive data set for the patients. One of the biggest messages of our study is that lack of uniformity in some clinical and demographic data of participants may become an obstacle in approaching FMF patients and understanding this complex disease