NDM Data Sample Analysis: Final Results (2) Option C: Regression Analysis 5th December 2012

Contents In-Sample Results as per previous presentation i.e., Winter/Summer Modelling on 2008/2009 Data AQ-Corrected Out-of-Sample Model fit using 2009/2010 data Conclusion

OUT-OF-SAMPLE RESULTS 2009/2010 Gas year

Out-of-Sample Results: EUC1 Graphical Output Oct 09-Mar 10 XoServe AQ NDM Sample AQ MAPE 7.68% 4,134,029 3,803,042 Average BIAS 7.12% R² 97.87%

Out-of-Sample Results: EUC2 Graphical Output Oct 09-Mar 10 XoServe AQ NDM Sample AQ MAPE 16.23% 16,592,319 5,350,971 Average BIAS 9.62% R² 88.26%

Out-of-Sample Results: EUC3 Graphical Output Oct 09-Mar 10 XoServe AQ NDM Sample AQ MAPE 21.89% 45,173,231 20,269,895 Average BIAS 19.87% R² 93.89%

Out-of-Sample Results: EUC4 Graphical Output Oct 09-Mar 10 XoServe AQ NDM Sample AQ MAPE 13.67% 440,453,374 214,592,141 Average BIAS 12.12% R² 93.81%

Conclusion Out-of-Sample data fit for Oct-09 to Mar-10 only as significant level shift (i.e., 30%+) observed. This is could be because of Regression coefficients needing to be re-estimated. Out-of-sample accuracy results poor. This could be because of the number of meters changing year on year Lack of normalisation by AQ prior to modelling Significant behavioural change not captured by analysis AQ re-base issue