IDEAS home Printed from https://ideas.repec.org/a/kap/pubcho/v171y2017i3d10.1007_s11127-017-0439-7.html
   My bibliography  Save this article

Are two better than one? A note

Author

Listed:
  • Ruth Ben-Yashar

    (Bar Ilan University)

  • Shmuel Nitzan

    () (Bar Ilan University)

Abstract

This note examines the possibility of extending the Condorcet Jury Theorem (CJT) by relaxing the assumption of homogeneous individual decision-making skills. Our main result provides two sufficient conditions for advantageous extension of a group. These conditions are referred to as (Weak) “Two Are Better than One” (WTBO) and TBO. The latter requires that the average decision-making competence of the two added members exceeds those of any existing group member. The weaker condition WTBO requires that the sum of the optimal weights of the two added members is larger than the optimal weight of any existing group member. Immediate special cases of our result include CJT settings wherein decision-making skills are assumed to be identical as well as situations wherein such skills are of two types: low and high.

Suggested Citation

  • Ruth Ben-Yashar & Shmuel Nitzan, 2017. "Are two better than one? A note," Public Choice, Springer, vol. 171(3), pages 323-329, June.
  • Handle: RePEc:kap:pubcho:v:171:y:2017:i:3:d:10.1007_s11127-017-0439-7
    DOI: 10.1007/s11127-017-0439-7
    as

    Download full text from publisher

    File URL: http://link.springer.com/10.1007/s11127-017-0439-7
    File Function: Abstract
    Download Restriction: Access to full text is restricted to subscribers.

    As the access to this document is restricted, you may want to search for a different version of it.

    References listed on IDEAS

    as
    1. Ruth Ben-Yashar & Shmuel Nitzan, 2014. "On the significance of the prior of a correct decision in committees," Theory and Decision, Springer, vol. 76(3), pages 317-327, March.
    2. Drora Karotkin & Jacob Paroush, 2003. "Optimum committee size: Quality-versus-quantity dilemma," Social Choice and Welfare, Springer;The Society for Social Choice and Welfare, vol. 20(3), pages 429-441, June.
    3. Ladha, Krishna K., 1995. "Information pooling through majority-rule voting: Condorcet's jury theorem with correlated votes," Journal of Economic Behavior & Organization, Elsevier, vol. 26(3), pages 353-372, May.
    4. Ben-Yashar, Ruth & Danziger, Leif, 2011. "Symmetric and asymmetric committees," Journal of Mathematical Economics, Elsevier, vol. 47(4-5), pages 440-447.
    5. Ruth Ben-Yashar & Mor Zahavi, 2011. "The Condorcet jury theorem and extension of the franchise with rationally ignorant voters," Public Choice, Springer, vol. 148(3), pages 435-443, September.
    6. Ruth Ben-Yashar, 2014. "The generalized homogeneity assumption and the Condorcet jury theorem," Theory and Decision, Springer, vol. 77(2), pages 237-241, August.
    7. Ruth Ben-Yashar & Jacob Paroush, 2000. "A nonasymptotic Condorcet jury theorem," Social Choice and Welfare, Springer;The Society for Social Choice and Welfare, vol. 17(2), pages 189-199.
    8. Franz Dietrich & Christian List, 2013. "Propositionwise judgment aggregation: the general case," Social Choice and Welfare, Springer;The Society for Social Choice and Welfare, vol. 40(4), pages 1067-1095, April.
    9. Scott Feld & Bernard Grofman, 1984. "The accuracy of group majority decisions in groups with added members," Public Choice, Springer, vol. 42(3), pages 273-285, January.
    10. Lloyd Shapley & Bernard Grofman, 1984. "Optimizing group judgmental accuracy in the presence of interdependencies," Public Choice, Springer, vol. 43(3), pages 329-343, January.
    11. Daniel Berend & Jacob Paroush, 1998. "When is Condorcet's Jury Theorem valid?," Social Choice and Welfare, Springer;The Society for Social Choice and Welfare, vol. 15(4), pages 481-488.
    12. Nitzan, Shmuel & Paroush, Jacob, 1982. "Optimal Decision Rules in Uncertain Dichotomous Choice Situations," International Economic Review, Department of Economics, University of Pennsylvania and Osaka University Institute of Social and Economic Research Association, vol. 23(2), pages 289-297, June.
    13. Eyal Baharad & Ruth Ben-Yashar, 2009. "The robustness of the optimal weighted majority rule to probability distortion," Public Choice, Springer, vol. 139(1), pages 53-59, April.
    Full references (including those not matched with items on IDEAS)

    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:kap:pubcho:v:171:y:2017:i:3:d:10.1007_s11127-017-0439-7. See general information about how to correct material in RePEc.

    For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: (Sonal Shukla) or (Springer Nature Abstracting and Indexing). General contact details of provider: http://www.springer.com .

    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 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.

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

    IDEAS is a RePEc service hosted by the Research Division of the Federal Reserve Bank of St. Louis . RePEc uses bibliographic data supplied by the respective publishers.