SWARA, EDAS, MARCOS yöntemleri ile tedarikçi değerlendirme modeli: Otelcilik sektöründe bir uygulama
Supplier evaluation model with SWARA, EDAS, MARCOS methods: An application in the hotel industry
Yazar: AYŞE ÜNLÜ
Danışman: DOÇ. DR. GÜLTEKİN ÇAĞIL
Sakarya Üniversitesi / Fen Bilimleri Enstitüsü / Endüstri Mühendisliği Ana Bilim Dalı
Derece: Yüksek Lisans, 2024
Konu: Endüstri ve Endüstri Mühendisliği = Industrial and Industrial Engineering

Özet:
Otelcilik, turizm sektörünün önemli bir parçası olmakla birlikte ekonomik büyümeye, istihdama ve ülkenin gelişmesine katkı sağlamaktadır. Otelcilik sektöründe yer alan işletmelerin bu faktörleri yerine getirebilmesi için, Tedarik Zinciri Yönetimi büyük önem arz etmektedir. Bu sektörde yer alan işletmelerin Tedarik Zinciri Yönetimi'ndeki başarısı ise doğru tedarikçilerle iş birliği içerisinde olmalarına dayanmaktadır. Dolayısıyla otel işletmelerinin tedarikçi seçim süreci stratejik açıdan önem taşımaktadır. Bu çalışmada, otelcilik sektörü işletmelerinin tedarik zinciri sorunlarından biri olan tedarikçi seçimi karar verme süreci ele alınarak incelenmektedir. Çalışmada ilk olarak çeşitli sektörlerdeki tedarikçi seçim kriterleri, yöntemleri ve stratejileri ile bunların otelcilik sektöründe kullanılabilirliğine ilişkin bir literatür araştırması gerçekleştirilmiştir. Devamında otellerde çalışan satın alma profesyonelleri ile gerçekleştirilen görüşmeler neticesinde otelcilik sektörüne özgü bu çalışmada kullanılan tedarikçi seçim kriterleri oluşturulmuştur. Bu kriterler; kalite, satın alma sonrası hizmet, teslimat, fiyat, teknik yeterlilik, güncel kriterler, esneklik, sektörel durum ve yönetimsel yaklaşım gibi kriterlere dayanarak belirlenmiştir. Belirlenen kriterlerin otelcilik sektöründe geçerliliğini tespit etmek amacıyla bir anket çalışması yürütülmüştür. Bu çerçevede, çalışma kapsamında ele alınacak evren, örneklem büyüklüğü ve örnekleme yöntemi belirlenmiştir. Belirlenen tedarikçi seçim kriterlerinin otelcilik sektörü işletmeleri için geçerliliğini değerlendirmek üzere Haziran 2023'te Türkiye'deki 20.116 oteli temsil eden 68 otelden oluşan bir örneklem oluşturulmuş ve tesadüfi örnekleme yöntemine dayalı çevrimiçi ortamda anket çalışması düzenlenmiştir. Bu anketin bulguları, bu çalışmada kullanılan tedarikçi seçim kriterlerinin geçerliliğini desteklemiş ve otelcilik sektörünün satın alma departmanlarında çalışan profesyoneller tarafından dikkate alındığını göstermiştir. Geçerliliği kanıtlanan tedarikçi seçim kriterleri, satın alma profesyonellerinin bilgi birikimi ve tecrübeleri doğrultusunda kriterlerin önem derecesini belirleyeceği için SWARA yöntemi kullanılarak ağırlıklandırılmıştır. Çalışmanın bu noktasında ise veriye ulaşım kolaylığı açısında Sakarya'da konaklama imkânı sunan otel işletmelerinde uygulamaya yer verilmiştir. Uygulama sonuçlarına göre otelcilik sektöründeki işletmelerin tedarikçi seçiminde ürünün kalitesi, müşterinin üründen memnuniyeti ve ürüne uygulanan kalite kontrol kriterlerine daha fazla, karbon ayak izi, tedarikçi başarı performansı ve tedarikçi ekonomik performansı kriterlerine ise daha az önem verdiği tespit edilmiştir. Tespit edilen kriterlerin ağırlıkları, EDAS ve MARCOS yöntemleri bir otel işletmesinin ihtiyaçlarına yönelik en uygun tedarikçiyi seçmek üzere kullanılmış, iki yöntemle elde edilen sıralamalar karşılaştırılmış ve otel işletmesinin belirlediği standartlara göre en uygun tedarikçi seçimi yapılmıştır. Çok alternatifli karmaşık karar verme problemlerinde birden fazla kritere göre öncelik belirlemeyi amaç edinen bu yöntemler, seçilen otel işletmesinin alternatif tedarikçilerini değerlendirirken tarafsız bir yaklaşım sağlamış ve bütün alternatiftedarikçileri sıralayarak en uygun tedarikçinin belirlenmesine katkıda bulunmuştur. Elde edilen değerler sonuç kısmında tartışılmıştır.

Abstract:
Hotel management, an indispensable part of the tourism sector, significantly contributes to economic growth, employment creation, and the country's development in general. Supply chain management is essential for hotel businesses as it helps them sustain these contributions and maintain their competitive advantages. The success of the enterprises in this sector in Supply Chain Management is based on their cooperation with suitable suppliers. For this reason, the supplier selection process of hotel businesses is strategically essential and requires a comprehensive evaluation of decision-making processes. While making these strategic decisions, managers and professionals in the businesses carry out comprehensive and multidimensional analyses to select the most suitable one for the needs of the business among various suppliers. These processes often stand out as complex decision-making processes that must be managed objectively and rationally. In this context, multi-criteria decision-making (MCDM) methods are used as an effective tool to solve complex problems such as supplier selection.
MCDM methods are constantly evolving and becoming more comprehensive by combining different approaches to deal with the uncertainties that arise in the identification, ranking, and weighting of criteria in supplier selection. The supplier selection process involves a detailed analysis of more than one stage. This process starts with the definition of the decision problem by considering the current situation and needs of the business. This is followed by determining qualitative and quantitative supplier selection criteria that should be evaluated per the business objectives. The importance of each criterion is revealed by calculating the criteria weights. Then, alternative suppliers are evaluated according to these criteria, and each alternative is ranked according to its performance. In the final stage, the most suitable final supplier is selected based on all analyses and ranking results. This process directly contributes to operational efficiency and customer satisfaction.
In the literature, multi-criteria decision-making (MCDM) methods are widely used to solve various problems faced by enterprises operating in the tourism sector. However, the supplier selection problem addressed in this study has been analyzed and solved using various MCDM methods in different sectors. However, the number of studies on supplier selection in the hospitality sector, considered within the tourism sector, is quite limited compared to other sectors. In addition, when the studies in the literature are analyzed, there is no study in which the MCDM methods used together in this study are handled in the same way. In particular, studies on the tourism sector primarily focus on a few criteria, such as weighting methods and alternative ranking methods. On the other hand, this study considered different criteria weighting methods and alternative ranking methods, and a more comprehensive analysis was carried out.
This study examines the supplier selection decision-making process, which is one of the supply chain problems of hospitality sector enterprises. First, a literature reviewwas conducted on supplier selection criteria, methods, and strategies in various sectors and their usability in the hospitality sector. Then, as a result of interviews with purchasing professionals working in hotels, supplier selection criteria specific to the hospitality sector used in this study were created. These criteria are based on quality, post-purchase service, delivery, price, technical competence, current criteria, flexibility, sectoral situation, and managerial approach. A survey was conducted to determine the validity of the criteria in the hotel industry.
The survey consists of two parts: demographic questions and questions questioning the appropriateness of the criteria determined for supplier selection. The first part of the questionnaire includes questions about the demographic information of the hotel purchasing professionals participating in the study, such as age, education level, working time in the tourism sector, working time in the hotel purchasing department, and general information about the hotel they work in such as the geographical region where the hotel is located, the number of stars of the hotel, the type of hotel ownership, and the number of active suppliers. In the second part of the questionnaire are questions about the appropriateness of the criteria determined for supplier selection. These questions were prepared using the Likert scale, one of the most widely used scales for measuring attitudes and behaviors.
The population, sample size, and sampling method to be addressed within the scope of the study were determined. In order to assess the validity of supplier selection criteria for hospitality businesses, a sample of 68 hotels representing 20,116 hotels in Turkey was formed in June 2023, and an online survey was organized based on a random sampling method. The survey was conducted between June 2023 and December 2023, and 115 purchasing professionals participated. The findings of this survey supported the validity of the supplier selection criteria used in this study. They showed that they are taken into account by professionals working in the purchasing departments of the hospitality industry.
The validated supplier selection criteria were weighted using the SWARA method since purchasing professionals will determine the importance of the criteria in line with their knowledge and experience. At this point of the study, an application was made in hotel enterprises providing accommodation services in Sakarya for ease of access to data. According to the results of the application, it was determined that the five critical criteria in the supplier selection of the enterprises in the hotel sector are product quality, customer satisfaction with the product, quality control applied to the product, purchase price of the product, and accessibility to the supplier. On the other hand, the five criteria that are not important are supplier-customer portfolio, green criteria, the economic power of the supplier, supplier success performance, and carbon footprint. According to the results of the study, it is seen that the quality of the product, customer satisfaction with the product, and quality control criteria applied to the product, which are directly related to quality criteria, are more prioritized in supplier selection compared to others. This situation reveals hotel businesses' importance in providing quality services and products to their customers. Quality criteria were followed by the product's purchase price, which directly affects the cost and profit of the hotel business. These findings indicate that product purchase price is not the sole determinant in supplier selection and should be evaluated as a whole with quality criteria. The supplier accessibility criterion, which follows the product purchase price criterion, also emphasizes the need for the supplier to be accessible and to be able to communicate when needed in order to carry out the supply chain processes without disruption. It was also found that criteria related to the sectoral status of the supplier, such asxxv
customer portfolio, economic strength, and success performance, were less critical in supplier selection. In addition, current criteria such as green criteria and carbon footprint, which have become increasingly important in tourism and supplier selection in recent years, were less important than other criteria in this study. These results may be related to the hotel businesses' objectives and the sector's dynamic structure.
The weights of the criteria, as well as EDAS and MARCOS methods, were used to select the most suitable supplier for the needs of a hotel business. EDAS and MARCOS methods were used to select the most suitable supplier for hotel standards among four alternative suppliers selected by the decision maker working in the purchasing department of the hotel. In complex decision-making problems with multiple alternatives, the ranking obtained with these two methods, which aim to determine priority over multiple criteria, is Supplier C, Supplier B, Supplier A, and Supplier D. Based on these rankings, it is concluded that cooperating with Supplier C among alternative suppliers is the most appropriate option for the hotel business and it is recommended to decide this direction.
The rankings obtained with the EDAS and MARCOS methods used in the study were compared with the rankings obtained with other methods such as TOPSIS, MOORA, ARAS, MAUT, MABAC, ROV, and WASPAS, and sensitivity analysis was performed. Through this analysis, the consistency of the methods used in the study was examined in detail. In addition, the Borda Counting method was also included in the study to evaluate the rankings holistically and rationally. The analysis conducted using the Borda Counting method concluded that the rankings obtained using the EDAS and MARCOS methods overlapped with those obtained using other methods. This finding supported the consistency and reliability of the methods used in the study. The findings are discussed in detail in the conclusion section.