Sethi model

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The Sethi model was developed by Suresh P. Sethi and describes the process of how sales evolve over time in response to advertising. [1] [2] The model assumes that the rate of change in sales depend on three effects: response to advertising that acts positively on the unsold portion of the market, the loss due to forgetting or possibly due to competitive factors that act negatively on the sold portion of the market, and a random effect that can go either way.

Contents

Suresh Sethi published his paper "Deterministic and Stochastic Optimization of a Dynamic Advertising Model" in 1983. [1] The Sethi model is a modification as well as a stochastic extension of the Vidale-Wolfe advertising model. [3] The model and its competitive and multi-echelon channel extensions have been used extensively in the literature. [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [20] [21] [22] [23] [24] [25] [26] [27] [28] [29] [30] [31] [32] [33] [34] [35] Moreover, some of these extensions have been also tested empirically. [6] [7] [10] [13]

Model

The Sethi advertising model or simply the Sethi model provides a sales-advertising dynamics in the form of the following stochastic differential equation:

.

Where:

Explanation

The rate of change in sales depend on three effects: response to advertising that acts positively on the unsold portion of the market via , the loss due to forgetting or possibly due to competitive factors that act negatively on the sold portion of the market via , and a random effect using a diffusion or White noise term that can go either way.

Example of an optimal advertising problem

Subject to the Sethi model above with the initial market share , consider the following objective function:

where denotes the sales revenue corresponding to the total market, i.e., when , and denotes the discount rate.

The function is known as the value function for this problem, and it is shown to be [2]

where

The optimal control for this problem is [2]

where

and

Extensions of the Sethi model

See also

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<span class="mw-page-title-main">Suresh P. Sethi</span> American mathematician

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References

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  2. 1 2 3 Sethi, S.P. (2021). Optimal Control Theory: Applications to Management Science and Economics. Fourth Edition. Springer. pp. 354-356. ISBN   978-3-319-98236-6 , 978-3-319-98237-3. http://doi.org/10.1007/978-3-319-98237-3
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  4. 1 2 3 Kennedy, Adrian Patrick; Sethi, Suresh P.; Siu, Chi Chung; Yam, Sheung Chi Phillip (2021-07-26). "Cooperative Advertising in a Dynamic Three-Echelon Supply Chain". Production and Operations Management. 30 (11): 3881–3905. doi:10.1111/poms.13487. ISSN   1059-1478. S2CID   236272112.
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  8. 1 2 Prasad, A.; Sethi, S. P. (2004). "Competitive Advertising under Uncertainty: Stochastic Differential Game Approach". Journal of Optimization Theory and Applications. 123 (1): 163–185. doi:10.1023/B:JOTA.0000043996.62867.20. S2CID   121005830.
  9. 1 2 Bass, F. M.; Krishamoorthy, A.; Prasad, A.; Sethi, S. P. (2005). "Generic and Brand Advertising Strategies in a Dynamic Duopoly". Marketing Science. 24 (4): 556–568. doi:10.1287/mksc.1050.0119. S2CID   17054876.
  10. 1 2 3 4 Naik, P. A.; Prasad, A.; Sethi, S. P. (2008). "Building Brand Awareness in Dynamic Oligopoly Markets". Management Science. 54 (1): 129–138. CiteSeerX   10.1.1.510.731 . doi:10.1287/mnsc.1070.0755. S2CID   18908145.
  11. 1 2 Erickson, G. M. (2009). "An Oligopoly Model of Dynamic Advertising Competition". European Journal of Operational Research. 197: 374–388. doi:10.1016/j.ejor.2008.06.023.
  12. Prasad, A.; Sethi, S. P. (2009). "Integrated Marketing Communications in Markets with Uncertainty and Competition". Automatica. 45 (3): 601–610. doi:10.1016/j.automatica.2008.09.018. S2CID   8385913.
  13. 1 2 3 4 Erickson, G. M. (2009). "Advertising Competition in a Dynamic Oligopoly with Multiple Brands". Operations Research. 57 (5): 1106–1113. doi:10.1287/opre.1080.0663.
  14. 1 2 Rong, Zhang; Qingzhong, Ren (May 2013). "Equivalence between Sethi advertising model and a scalar LQ differential game". 2013 25th Chinese Control and Decision Conference (CCDC). pp. 1244–1247. doi:10.1109/ccdc.2013.6561115. ISBN   978-1-4673-5534-6. S2CID   26614539.
  15. 1 2 He, X.; Prasad, A.; Sethi, S.P. (2009). "Cooperative Advertising and Pricing in a Stochastic Supply Chain: Feedback Stackelberg Strategies". Production and Operations Management. 18 (1): 78–94. doi:10.1111/j.1937-5956.2009.01006.x. S2CID   15522449. SSRN   1069063.
  16. 1 2 He, X.; Prasad, A.; Sethi, S.P.; Gutierrez, G. (2007). "A Survey of Stackelberg Differential Game Models in Supply and Marketing Channels". Journal of Systems Science and Systems Engineering. 16 (4): 385–413. doi:10.1007/s11518-007-5058-2. S2CID   11443159. SSRN   1069162.
  17. 1 2 Sethi, S.P.; Prasad, A.; He, X. (2008). "Optimal Advertising and Pricing in a New-Product Adoption Model". Journal of Optimization Theory and Applications. 139 (2): 351–360. doi:10.1007/s10957-008-9472-5. S2CID   16181059.
  18. 1 2 3 Krishnamoorthy, A., Prasad, A., Sethi, S.P. (2009). Optimal Pricing and Advertising in a Durable-Good Duopoly. European Journal of Operational Research.
  19. 1 2 3 Bensoussan, A., Chen, S., Chutani, A., Sethi, S.P., Siu, C.C., and Yam, S.C.P., "Feedback Stackelberg-Nash Equilibria in Mixed Leadership Games with an Application to Cooperative Advertising," SIAM Journal on Control and Optimization, 2019, 57(5), 3413-3444. SSRN 3493916.
  20. 1 2 3 4 Chutani A. and Sethi, S.P., "A Feedback Stackelberg Game of Cooperative Advertising in a Durable Goods Oligopoly," Dynamic Games in Economics, 13, J.L. Haunschmied, V. Veliov, and S. Wrzaczek (Eds.), Springer-Verlag Berlin Heidelberg, 2014, 89-114.
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  22. 1 2 Prasad, A., Sethi, S.P., and Naik, P., "Understanding the Impact of Churn in Dynamic Oligopoly Markets," Automatica, 48, 2012, 2882-2887.
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  24. 1 2 Chutani, A. and Sethi, S.P., "Optimal Advertising and Pricing in a Dynamic Durable Goods Supply Chain," Journal of Optimization Theory and Applications, 154(2), 2012, 615-643.SSRN 1898309.
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  26. 1 2 3 Krishnamoorthy, A., Prasad, A., and Sethi, S.P., "Optimal Pricing and Advertising in a Durable-Good Duopoly," European Journal of Operations Research, 200(2), 2010, 486-497. SSRN 1114989.
  27. 1 2 Prasad, A., Sethi, S.P., and Naik, P., "Optimal Control of an Oligopoly Model of Advertising," Proceedings of the 13th IFAC Symposium on Information Control Problems in Manufacturing (INCOM '09), Moscow, Russia, June 3–5, 2009. SSRN 1376394.
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  29. Kennedy, A.P., Sethi, S.P., Siu, C.C., and Yam, S.C.P., “Cooperative advertising in a dynamic three-echelon supply chain,” Production and Operations Management, 30(11), 2021, 3881–3905.
  30. Bensoussan, A., Chen, S., Chutani, A., Sethi, S.P., Siu, C.C., and Yam, S.C.P., “Feedback Stackelberg-Nash Equilibria in Mixed Leadership Games with an Application to Cooperative Advertising”, SIAM Journal on Control and Optimization, 57(5), 2019, 3413-3444.
  31. Han, Jinhui; Sethi, Suresh P.; Siu, Chi Chung; Yam, Sheung Chi Phillip (2023-01-11). "Co-op advertising in randomly fluctuating markets". Production and Operations Management. 32 (6): 1617–1635. doi:10.1111/poms.13929. ISSN   1059-1478.
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  34. He, Xiuli; Krishnamoorthy, Anand; Prasad, Ashutosh; Sethi, Suresh P. (2011-01-01). "Retail competition and cooperative advertising". Operations Research Letters. 39 (1): 11–16. doi:10.1016/j.orl.2010.10.006. ISSN   0167-6377. S2CID   15113829.
  35. Kennedy, Adrian; Prasad, Ashutosh; Sethi, Suresh; Siu, Chi Chung; Yam, S. C. P. (2022-09-02). "Optimal Advertising and Product Durability Decisions in New Product Diffusion". Rochester, NY.