tailieunhanh - Gold sales forecasting: The box-Jenkins methodology

The study employs the Box-Jenkins Methodology to forecast South African gold sales. For a resource economy like South Africa where metals and minerals account for a high proportion of GDP and export earnings, the decline in gold sales is very disturbing. Box-Jenkins time series technique was used to perform time series analysis of monthly gold sales for the period January 2000 to June 2013 with the following steps: model identification, model estimation, diagnostic checking and forecasting. Furthermore, the prediction accuracy is tested using mean absolute percentage error (MAPE). From the analysis, a seasonal ARIMA(4,1,4)×(0,1,1) 12 was found to be the “best fit model” with an MAPE value of 11% indicating that the model is fit to be used to predict or forecast future gold sales for South Africa. In addition, the forecast values show that there will be a decrease in the overall gold sales for the first six months of 2014. It is hoped that the study will help the public and private sectors to understand the gold sales or output scenario and later plan the gold mining activities in South Africa. Furthermore, it is hoped that this research paper has demonstrated the significance of Box-Jenkins technique for this area of research and that they will be applied in the future. | Risk governance control financial markets institutions Volume 7 Issue 1 Winter 2017 GOLD SALES FORECASTING THE BOX-JENKINS METHODOLOGY Johannes Tshepiso Tsoku Nonofo Phukuntsi Daniel Metsileng North West University South Africa Abstract The study employs the Box-Jenkins Methodology to forecast South African gold sales. For a resource economy like South Africa where metals and minerals account for a high proportion of GDP and export earnings the decline in gold sales is very disturbing. Box-Jenkins time series technique was used to perform time series analysis of monthly gold sales for the period January 2000 to June 2013 with the following steps model identification model estimation diagnostic checking and forecasting. Furthermore the prediction accuracy is tested using mean absolute percentage error MAPE . From the analysis a seasonal ARIMA 4 1 4 x 0 1 1 was found to be the best fit model with an MAPE value of 11 indicating that the model is fit to be used to predict or forecast future gold sales for South Africa. In addition the forecast values show that there will be a decrease in the overall gold sales for the first six months of 2014. It is hoped that the study will help the public and private sectors to understand the gold sales or output scenario and later plan the gold mining activities in South Africa. Furthermore it is hoped that this research paper has demonstrated the significance of Box-Jenkins technique for this area of research and that they will be applied in the future. Keywords Gold Sales ARIMA Box-Jenkins GDP MAPE JEL Classification C38 L52 DOI rgcv7i1art7 1. INTRODUCTION The Box-Jenkins methodology has gained more popularity since their book publication in 1970. The Box-Jenkins method which does not require establishing assumptions on the interdependence of variables could be used to test applicability on data series undergoing dynamic fluctuation. More significantly this technique does not introduce too much personal bias into the .