PERBANDINGAN METODE KUALITATIF, KUANTITATIF DAN COMBINE METHOD TERHADAP TERJADINYA STOCK OUT DAN OVER STOCK
Abstract
Forecast conducted generally based on data contained in the past that were analyzed by using certain method. This research purposed to analyzed the effect of using the best forecasting method to over stock and stock out. The item contained in two convinience supermarkets which different using quantitative method (Average, Single Moving Average and Single Exponential Smoothing), Qualitative Method (Pure Judgement) and combine method (a combination of quantitative and qualitative). To determine the best method to use three Forecasting error methods is Mean Absolute Error (MAE), Mean Square Error (MSE) and Standard Deviation Error (SDE). Although in two different areas and have the number of demand which extremely different, but the choosen method between two convenience supermarkets are same quantitative method eith SES method. Convenience Supermarket A prefer to stock out than over stock, but convenience Supermarket B prefer to has more items in inventory.
Keywords: Forecasting, Forecasting Error, Stock Out, Over Stock.
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