Tuğçe EKİZ YILMAZ, Güçkan YAPAR, İDİL YAVUZ

KESİKLİ TALEPLERİN TAHMİNLENMESİNDE ATA METOT VE CROSTON TEMELLİ METOTLARIN KARŞILAŞTIRILMASI

Kesikli talep tahmini, şirketler ve ticari faaliyetler için çok önemlidir. Son zamanlarda, birçok araştırmacı kesikli talep için tahmin yöntemlerine odaklandı ve çeşitli tahmin teknikleri önerdiler. Bu önerilen teknikler arasında öne çıkan yöntemler, üssel düzleştirmeye dayanan Croston yöntemi ve bu yöntemin iki türevi olan SBA (Syntetos-Boylan Yaklaşımı) ve SBJ (Shale-Boylan-Johnston Yaklaşımı) metotlarıdır.e Croston yöntemi, kesikli talep ve envanter (stok) kontrolünün tahmininde yaygın olarak kullanılmaktadır. Bu talepler genellikle sıfır değerini içerdiğinden, bu verilerde Croston tarafından geliştirilen öne çıkan metodun kullanılması kaçınılmaz hale gelir. Bununla birlikte; bu yöntemin, yanlı tahminler üretmek gibi bazı eksiklikleri vardır ve bu sebeple türevleri önerilmiştir. ATA metot, üssel düzleştirmeye alternatif olarak yeni geliştirilen bir tahmin metodudur. Bu çalışmada, kesikli talebin tahmin edilmesi için bir ATA yönteminin bir modifikasyonunu öneriyoruz. Önerilen yaklaşımın sonuçlarını, Croston ve kesikli talep tahmini için kullanılan diğer tahmin yöntemleriyle karşılaştıracağız.

Anahtar Kelimeler:

Croston metot, Envanter Kontrolü, Kesikli Talep, Talep tahminlemesi, Üssel düzleştirme, Zaman serisi

COMPARISON OF ATA METHOD AND CROSTON BASED METHODS ON FORECASTING OF INTERMITTENT DEMAND

Intermittent demand forecasting is crucial for firms and commercial activities. Recently, many researchers have focused on forecasting methods for intermittent demand and proposed various forecasting techniques. The most prominent methods among these proposed techniques are the Croston method, which is based on exponential smoothing, and its two popular variations: SBA (Syntetos-Boylan Approximation), SBJ (Shale-Boylan-Johnston Approximation). Croston method is widely used in forecasting of intermittent demand and inventory (stock) control. Since these demands usually include zero values, using the ground breaking method developed by Croston in this data becomes inevitable. Nevertheless, there are some shortcomings to this method such as producing biased forecasts and for this reason its variations have been proposed. ATA method is a recently developed forecasting method which is an alternative to exponential smoothing. In this paper we propose a modification of ATA method that can be used for forecasting of intermittent demand. We will compare the results of the proposed approach to those of Croston and other forecasting methods used for intermittent demand forecasting.

Keywords:

Exponential smoothing, Demand forecasting, Time series, Croston method, Intermittent demand, Inventory control,

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