IDEAS home Printed from https://ideas.repec.org/p/cwl/cwldpp/1552.html
   My bibliography  Save this paper

Informational Herding and Optimal Experimentation

Author

Listed:
  • Lones Smith

    (Dept. of Economics, University of Michigan)

  • Peter Norman Sorensen

    (Department of Economics, University of Copenhagen)

Abstract

We show that far from capturing a formally new phenomenon, informational herding is really a special case of single-person experimentation -- and 'bad herds' the typical failure of complete learning. We then analyze the analogous team equilibrium, where individuals maximize the present discounted welfare of posterity. To do so, we generalize Gittins indices to our non-bandit learning problem, and thereby characterize when contrarian behaviour arises: (i) While herds are still constrained efficient, they arise for a strictly smaller belief set. (ii) A log-concave log-likelihood ratio density robustly ensures that individuals should lean more against their myopic preference for an action the more popular it becomes.

Suggested Citation

  • Lones Smith & Peter Norman Sorensen, 2006. "Informational Herding and Optimal Experimentation," Cowles Foundation Discussion Papers 1552, Cowles Foundation for Research in Economics, Yale University.
    • Handle: RePEc:cwl:cwldpp:1552
    as

    Download full text from publisher

    File URL: https://cowles.yale.edu/sites/default/files/files/pub/d15/d1552.pdf
    Download Restriction: no
    ---><---

    Other versions of this item:

    References listed on IDEAS

    as
    1. Philippe Aghion & Patrick Bolton & Christopher Harris & Bruno Jullien, 1991. "Optimal Learning by Experimentation," The Review of Economic Studies, Review of Economic Studies Ltd, vol. 58(4), pages 621-654.
    2. Matthew Doyle, 2010. "Informational externalities, strategic delay, and optimal investment subsidies," Canadian Journal of Economics, Canadian Economics Association, vol. 43(3), pages 941-966, August.
    3. Rothschild, Michael, 1974. "A two-armed bandit theory of market pricing," Journal of Economic Theory, Elsevier, vol. 9(2), pages 185-202, October.
    4. Xavier Vives, 1993. "How Fast do Rational Agents Learn?," The Review of Economic Studies, Review of Economic Studies Ltd, vol. 60(2), pages 329-347.
    5. Bikhchandani, Sushil & Hirshleifer, David & Welch, Ivo, 1992. "A Theory of Fads, Fashion, Custom, and Cultural Change in Informational Cascades," Journal of Political Economy, University of Chicago Press, vol. 100(5), pages 992-1026, October.
    6. Lones Smith & Peter Sorensen, 2000. "Pathological Outcomes of Observational Learning," Econometrica, Econometric Society, vol. 68(2), pages 371-398, March.
    7. Chamley, Christophe & Gale, Douglas, 1994. "Information Revelation and Strategic Delay in a Model of Investment," Econometrica, Econometric Society, vol. 62(5), pages 1065-1085, September.
    8. McLennan, Andrew, 1984. "Price dispersion and incomplete learning in the long run," Journal of Economic Dynamics and Control, Elsevier, vol. 7(3), pages 331-347, September.
    9. Sgroi, Daniel, 2002. "Optimizing Information in the Herd: Guinea Pigs, Profits, and Welfare," Games and Economic Behavior, Elsevier, vol. 39(1), pages 137-166, April.
    10. James Dow, 1991. "Search Decisions with Limited Memory," The Review of Economic Studies, Review of Economic Studies Ltd, vol. 58(1), pages 1-14.
    11. Amir, Rabah, 1996. "Sensitivity analysis of multisector optimal economic dynamics," Journal of Mathematical Economics, Elsevier, vol. 25(1), pages 123-141.
    12. Abhijit V. Banerjee, 1992. "A Simple Model of Herd Behavior," The Quarterly Journal of Economics, President and Fellows of Harvard College, vol. 107(3), pages 797-817.
    13. Burdett, Kenneth, 1996. "Truncated means and variances," Economics Letters, Elsevier, vol. 52(3), pages 263-267, September.
    Full references (including those not matched with items on IDEAS)

    Citations

    Citations are extracted by the CitEc Project, subscribe to its RSS feed for this item.
    as


    Cited by:

    1. Jacob K. Goeree & Thomas R. Palfrey & Brian W. Rogers & Richard D. McKelvey, 2007. "Self-Correcting Information Cascades," The Review of Economic Studies, Review of Economic Studies Ltd, vol. 74(3), pages 733-762.
    2. Alessandro Lizzeri & Marciano Siniscalchi, 2008. "Parental Guidance and Supervised Learning," The Quarterly Journal of Economics, President and Fellows of Harvard College, vol. 123(3), pages 1161-1195.
    3. Matthew Doyle, 2010. "Informational externalities, strategic delay, and optimal investment subsidies," Canadian Journal of Economics, Canadian Economics Association, vol. 43(3), pages 941-966, August.
    4. Gleason, Kimberly C. & Mathur, Ike & Peterson, Mark A., 2004. "Analysis of intraday herding behavior among the sector ETFs," Journal of Empirical Finance, Elsevier, vol. 11(5), pages 681-694, December.
    5. Christos Koulovatianos & Leonard J. Mirman & Marc Santugini, 2006. "Investment in a Monopoly with Bayesian Learning," Vienna Economics Papers vie0603, University of Vienna, Department of Economics.
    6. S. Ali & Navin Kartik, 2012. "Herding with collective preferences," Economic Theory, Springer;Society for the Advancement of Economic Theory (SAET), vol. 51(3), pages 601-626, November.
    7. Christos Koulovatianos & Leonard J. Mirman & Marc Santugini, 2006. "Investment in a Monopoly with Bayesian Learning," Vienna Economics Papers 0603, University of Vienna, Department of Economics.

    Most related items

    These are the items that most often cite the same works as this one and are cited by the same works as this one.
    1. Vives, Xavier, 1997. "Learning from Others: A Welfare Analysis," Games and Economic Behavior, Elsevier, vol. 20(2), pages 177-200, August.
    2. Sobel, Joel, 2000. "Economists' Models of Learning," Journal of Economic Theory, Elsevier, vol. 94(2), pages 241-261, October.
    3. Bolton, P. & Harris, C., 1996. "Strategic Experimentation : A Revision," Other publications TiSEM 2cd2755d-6931-488f-948e-5, Tilburg University, School of Economics and Management.
    4. Bolton, P. & Harris, C., 1996. "Strategic Experimentation : A Revision," Discussion Paper 1996-27, Tilburg University, Center for Economic Research.
    5. Daron Acemoglu & Munther A. Dahleh & Ilan Lobel & Asuman Ozdaglar, 2011. "Bayesian Learning in Social Networks," The Review of Economic Studies, Review of Economic Studies Ltd, vol. 78(4), pages 1201-1236.
    6. Camargo, Braz, 2014. "Learning in society," Games and Economic Behavior, Elsevier, vol. 87(C), pages 381-396.
    7. Mira Frick & Ryota Iijima & Yuhta Ishii, 2020. "Stability and Robustness in Misspecified Learning Models," Cowles Foundation Discussion Papers 2235, Cowles Foundation for Research in Economics, Yale University.
    8. Mira Frick & Ryota Iijima & Yuhta Ishii, 2020. "Belief Convergence under Misspecified Learning: A Martingale Approach," Cowles Foundation Discussion Papers 2235R2, Cowles Foundation for Research in Economics, Yale University, revised Dec 2021.
    9. Klimenko, Mikhail M., 2004. "Industrial targeting, experimentation and long-run specialization," Journal of Development Economics, Elsevier, vol. 73(1), pages 75-105, February.
    10. Umberto Garfagnini & Bruno Strulovici, 2012. "Social Learning and Innovation Cycles (revision of DP#1516, The Dynamics of Innovation)," Discussion Papers 1546, Northwestern University, Center for Mathematical Studies in Economics and Management Science.
    11. Ali, S. Nageeb, 2018. "On the role of responsiveness in rational herds," Economics Letters, Elsevier, vol. 163(C), pages 79-82.
    12. Subir Bose & Gerhard Orosel & Marco Ottaviani & Lise Vesterlund, 2006. "Dynamic monopoly pricing and herding," RAND Journal of Economics, RAND Corporation, vol. 37(4), pages 910-928, December.
    13. Mira Frick & Ryota Iijima & Yuhta Ishii, 2020. "Belief Convergence under Misspecified Learning: A Martingale Approach," Cowles Foundation Discussion Papers 2235R3, Cowles Foundation for Research in Economics, Yale University, revised Apr 2022.
    14. Chamley, Christophe, 2004. "Delays and equilibria with large and small information in social learning," European Economic Review, Elsevier, vol. 48(3), pages 477-501, June.
    15. Davide Crapis & Bar Ifrach & Costis Maglaras & Marco Scarsini, 2017. "Monopoly Pricing in the Presence of Social Learning," Management Science, INFORMS, vol. 63(11), pages 3586-3608, November.
    16. Jonathan E. Alevy & Michael S. Haigh & John List, 2006. "Information Cascades: Evidence from An Experiment with Financial Market Professionals," NBER Working Papers 12767, National Bureau of Economic Research, Inc.
    17. Daron Acemoglu & Asuman Ozdaglar, 2011. "Opinion Dynamics and Learning in Social Networks," Dynamic Games and Applications, Springer, vol. 1(1), pages 3-49, March.
    18. Ali, S. Nageeb, 2018. "Herding with costly information," Journal of Economic Theory, Elsevier, vol. 175(C), pages 713-729.
    19. Celen, Bogachan & Hyndman, Kyle, 2006. "Endogenous Network Formation In the Laboratory," MPRA Paper 1440, University Library of Munich, Germany.
    20. Gill, David & Sgroi, Daniel, 2008. "Sequential decisions with tests," Games and Economic Behavior, Elsevier, vol. 63(2), pages 663-678, July.

    More about this item

    Keywords

    Bayesian learning; value function; herding; experimentation; log concavity; Gittins index; team equilibrium;
    All these keywords.

    JEL classification:

    • D83 - Microeconomics - - Information, Knowledge, and Uncertainty - - - Search; Learning; Information and Knowledge; Communication; Belief; Unawareness

    NEP fields

    This paper has been announced in the following NEP Reports:

    Statistics

    Access and download statistics

    Corrections

    All material on this site has been provided by the respective publishers and authors. You can help correct errors and omissions. When requesting a correction, please mention this item's handle: RePEc:cwl:cwldpp:1552. See general information about how to correct material in RePEc.

    If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.

    If CitEc recognized a bibliographic reference but did not link an item in RePEc to it, you can help with this form .

    If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your RePEc Author Service profile, as there may be some citations waiting for confirmation.

    For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: Brittany Ladd (email available below). General contact details of provider: https://edirc.repec.org/data/cowleus.html .

    Please note that corrections may take a couple of weeks to filter through the various RePEc services.

    IDEAS is a RePEc service. RePEc uses bibliographic data supplied by the respective publishers.