Forecasting and inventory management: Bridging the gap Opening session Aris A. Syntetos and John E. Boylan

- 2 - Outline EPSRC – EP/D062942/1 (Aris) 2 Agenda for our meeting 4 EPSRC – EP/F012632/1 (Aris and John) 3 Research background 1

- 3 - Research background (…1 of 3) n John’s research with Roy Johnston in forecasting and stock control, with particular emphasis on intermittent demands n Aris’ PhD under John’s supervision: ‘Forecasting of intermittent demand’ n Our work necessitated the clarification of what is ‘intermittent demand’ in operational terms?

- 4 - Research background (...2 of 3) n Consequent work in the classification of demand patterns for forecasting and stock control purposes Williams (1984 ) Eaves and Kingsman (2004)

- 5 - Research background (...3 of 3) n Joint work with John Croston resulted in the proposal of a theoretically sound categorisation solutions, for forecasting purposes only:  Further work into this area demonstrated the complexity arising due to the interaction between forecasting and stock control.

- 6 - EPSRC – EP/D062942/1 n On the development of theory-informed operationalised definitions of demand patterns n A simulation intensive investigation that aims at the development of useful, universally applicable, rules for classifying demand patterns n Theory-data loops to reflect the complexity of the problem and the interaction between forecasting and stock control n We will be talking more about this project later today: Forecasting – stock control interactions I (Aris and Zied) n This is a 2-year project started last October. n Very fruitful research area: four papers already submitted for peer review n John is contributing as part of the project review team.

- 7 - EP/D062942/1 - Industrial collaborators Brother International, UK Computer Science Corporation Valves Instrument Plus, Ltd

- 8 - Collaboration for Success through People (CSP)  EPSRC call under the CSP initiative for expanding the scope of curent projects through the exploitation of inter-disciplinary opportunities  Funds were made available for people based activities and exchanges  That resulted in our joint proposal (Aris and John) that led to our project  This is a 9-month project with no specific deliverables, other than exploring and hopefully utilising potential synergies, establishing longer-term contacts and identifying promising new avenues for further research  The aim of this project is to bring together the strengths of statistical and judgemental forecasting with the complementary benefits of System Dynamics (SD), to initiate a new research agenda for inventory modelling.

- 9 - Objectives - EP/F012632/1 The aim is reflected on the following objectives 1.To explore how statistical forecasting models (which focus on mean demand and forecast error variability) and System Dynamics (SD) models (which focus on changes in mean demand) can be integrated. 2.To explore the effects of judgemental forecasting (or judgemental adjustments to statistical forecasts) on levels and variability of forecasts and the potential for their incorporation in System Dynamics models. 3.To extend this investigation to examine the effect on inventory systems, for a range of inventory policies. 4.To examine how SD can be used to inform and educate those involved in judgemental forecasting.

Collaborators AcademicsInstitutionExpertise Professor John BoylanBCUCCo-ordination team Dr Aris SyntetosSalford UniversityCo-ordination team Dr Stephen Disney Cardiff UniversitySystem Dynamics Professor Henk Akkermans Tilburg UniversitySystem Dynamics Professor Leo Strijbosch Tilburg UniversityForecasting/Inventory Dr Tarkan Tan Eindhoven UniversityInventory Modelling Professor Nada Sanders Texas Christian Univ.Judgemental Forecasting Dr S (Vish) Viswanathan Nanyang UniversityForecasting/Inventory PractitionersCompanySpecialisation Dr Wolfgang SchutzSAF – AG Forecasting software Dr Stephan KolassaSAF – AG Forecasting software Dr Bob EberleinVentana Systems, IncSystem Dynamics Software ReviewersInstitutionExpertise Professor Paul GoodwinBath UniversityJudgemental forecasting Professor Brian DangerfieldSalford UniversitySystem Dynamics Supporters: Zied Babai, Mohammad Ali and Mona Mohammadipour

Meetings and dissemination  Physical meetings to be conducted between John and Aris and the other collaborators during the course of the project  We have also introduced web-based conference communications in order to: i) keep the costs down; ii) introduce some flexibility and the possibility for ad-hoc virtual meetings  A web-site hosted by the University of Salford has already been created  We are looking at making this facility an interactive mode of communicating and posting ideas  Progressive incorporation of the outcomes of our meetings, research findings etc  Any ideas that you may have in improving this facility would be very welcomed  Dissemination of our work through: System Dynamics Review (Wiley) and International Journal of Production Economics (Elsevier)

Initial meeting  One-hour discussion sessions where the group can be updated on latest developments, reflecting your perspective and expertise  Open and relaxed discussions allowing the time for constructive comments to be made and explore the synergies between the various areas  As we are all often working within fairly well defined small research communities, ‘basic’ questions would not do any harm – on the contrary they may facilitate a better understanding of the common ground between us  Breakfast is served from – am  The dinner tonight is at pm

Proposed timetable Sessions (Tuesday)Facilitator(s) Opening sessionJohn and Aris System DynamicsBrian Software perspective (Forecasting)Stephan Forecasting – stock control interactions IAris and Zied Forecasting – stock control interactions IILeo Forecasting – stock control interactions IIITarkan Session (Wednesday)Facilitator(s) System Dynamics – Bullwhip ISteve System Dynamics – Bullwhip II John and Mohammad Concluding sessionJohn and Aris

Looking forward to an exciting project Questions …?