ANALISIS METODE JUDGMENTAL FORECASTING DALAM MENINGKATKAN KEAKURATAN HASIL FORECASTING PT.PERTAMINA REFINERY UNIT II-DUMAI
Abstract
This research was apply at one of the largest oil companies in Indonesia. The aims of this research is to see the effect of several aspects of human judgment. Which aspects is used information and non-information, decision making background and individual or group decision making. Data collection was carried out by distributing questionnaires to respondents. Each respondent will get 2 types of questionnaires, a questionnare with information and questionnare non-information. . The analysis is done by comparing the magnitude of the error of each method with the smallest error criteria using Geometric Root Mean Squere Error method. After calculation for each respondent, it was found that the biggest error forecasting came from the respondents of individual novices with information and the smallest error come from questionnaires with group practitioner respondents with information. It can be concluded that for used of judgment in forecasting is expected to be carried out with considerations from various aspects so the result obtained can provide benefits for the company.
Keywords: Forecasting, Human Judgment, Judgmental Forecasting, GRMSE
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