CONCLUSION

Interest in the understanding and measurement of polarization is relatively recent. This chapter has reviewed some of the conceptual foundations of polarization; it has described how polarization can be measured in an economic, social, and/or hybrid socioeconomic perspective; it has reviewed briefly the empirical and theoretical polarization/conflict polarization literature; and it has distinguished polarization from inequality and other ways of considering distances between individuals and groups.

Given the increasing interest in the causes and effects of polarization, one would expect further advances in its understanding. On the measurement side, one can envisage, for instance, the development of techniques for decomposing polarization across socio­economic groups, components of welfare, and features of the welfare distribution (such as modal structure, inequality, and measures of overlap); for making robust comparisons of polarization across time and societies; and for performing statistical inference on the levels and rankings of polarization. One can also foresee advances in the understanding of polar­ization levels and polarization dynamics, regarding, for instance, the role and the impor­tance of socioeconomic changes (such as the effect of group sizes and distances) and the differential impact of alienation and identification across time. The dynamic impact of polarization on tensions and conflicts as well as the reverse impact are also plausible and important features of future research on polarization. Finally, the possible effect of growth, policy, and redistribution (in particular) on polarization, as opposed to other aspects of the income distribution, would also seem to constitute important areas for future research on polarization.

ACKNOWLEDGMENTS

The authors are grateful to Tony Atkinson, Francois Bourguignon, Satya Chakravarty, Joan Esteban, and Ignacio Permanyer Ugartemendia for helpful comments.

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