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Bivariate Radialsymmetric Kernel Density Estimation of Well-being Distribution and Poverty Index

Received: 9 June 2026     Accepted: 24 July 2026     Published: 5 September 2026
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Abstract

In two previous papers, we proposed two bivariate product kernel estimators for the bi-dimensional extension of the Foster, Greer and Thorbecke (FGT) index based respectively on classical and adaptive kernel. The Foster, Greer and Thorbecke (FGT) index was introduced in the literature for the purpose of a dominance approach to multidimensional poverty. The poverty measure utilized in this dominance method is fundamentally a generalization, from one to two dimensions, of this Foster, Greer and Thorbecke index with separate poverty aversion parameters for each dimension. This statistical method (the product kernel estimator) has the following main disadvantes: the curse of dimensionality, the complex selection of the bandwidth, and high computational costs. In this study, we focus on a bivariate radialsymmetric kernel estimator for the bi-dimensional extension of the Foster, Greer and Thorbecke index. Our new bivariate kernel estimator is developed with a classical bivariate kernel of Parzen-Rosenblatt of a probability density function (pdf) utilizing Riemann sums. We next provide complete asymptotic behaviour by establishing both almost-sure uniform and uniform mean square consistencies for the bivariate radialsymmetric kernel estimator. A simulation study indicates that the proposed bivariate kernel estimator performs favorably for small samples comparatively to the bivariate multiplicative kernel estimator.

Published in American Journal of Theoretical and Applied Statistics (Volume 15, Issue 5)
DOI 10.11648/j.ajtas.20261505.11
Page(s) 177-201
Creative Commons

This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.

Copyright

Copyright © The Author(s), 2026. Published by Science Publishing Group

Keywords

Bidimensional Poverty Index, Foster-Greer-Thorbecke (FGT) Measure, Bivariate Radialsymmetric Kernel Density Estimation, Nonparametric Estimation, Uniform Almost-sure Consistency, Riemann Sums, Well-being Distribution, Rate of Convergence

References
[1] Al Hassana Diallo, Youssou Ciss, Baradine Zakaria et al. "ON THE ADAPTIVE BI-DIMENSIONAL KERNEL DENSITY ESTIMATION OF WELL-BEING DISTRIBUTION AND POVERTY INDEX". Far East Journal of Theoretical Statistics, vol. 66, Aug. 2022, pp. 15-72.
[2] Alkire, S., & Foster, J. (2011). Counting and multidimensional poverty measurement. Journal of Public Economics, 95(7-8), 476-487, 2011.
[3] Atkinson, A.B., 1987. On the Measurement of Poverty. Econometrica, 55 (4), 749-764, 1987.
[4] Biewen, M. (2002). Bootstrap inference for inequality, mobility and poverty measurement. Journal of Economic Inequality, 1(1), 51-69, 2002.
[5] Bourguignon, F., & Chakravarty, S. R. (2003). The measurement of multidimensional poverty. Journal of Economic Inequality, 1(1), 25-49, 2003.
[6] Davidson, R., & Flachaire, E. (2007). Asymptotic and bootstrap inference for inequality and poverty measures. Journal of Econometrics, 141(1), 141-166, 2007.
[7] Duclos, J. Y., Sahn, D. E. and Younger, S. D. (2006). Robust multidimensional poverty comparison. Economic Journal, 113:943-968, 2006.
[8] Duclos, J. Y., Sahn, D. E. and Younger, S. D. (2006). Robust multidimensional spatial poverty comparisons in Ghana, Madagascar, and Uganda. World Bank Econ. Rev., 20(1), 91-113, 2006.
[9] Foster, J. E., Greer, J. and E. Thorbecke (1984) A class of decomposable poverty measures. Econometrica, 52:761-776, 1984.
[10] Foster, J. E. and Shorrocks, A.F. (1988) Poverty Orderings. Econometrica, 56, 173-177, 1988.
[11] Foster, J. E. and Shorrocks, A.F. (1988) Poverty Orderings and Welfare Dominance. Social Choice Welfare, 5, 179-198, 1988.
[12] Foster, J. E. and Shorrocks, A.F. (1988) Inequality and Poverty Orderings. European Economic Review, 32, 654-662, 1988.
[13] Dia, G.. Nonparametric estimation of income distribution and poverty index. C. R. Acad. Sci. Paris, Volume 346 (2008) no. 15-16, pp.907-912.
[14] H"ardle, W., M"uller, M. (1997). Multivariate and Semiparametric Kernel Regression. Sonderforschungsbereich 373: Quantification and Simulation of Economic Processes., 1997,26.
[15] Parzen, E. (1956). On estimation of a probability density function and mode. Annals of Mathematical Statistics, Volume 33, Issue 3:1065-1076, Sep. 1962.
[16] Schimek, M. G. (2000)., Smoothing and Regression. John Wiley & Sons Inc., New York, ed. 2000
[17] Scott, D. W. (2015). Multivariate Density Estimation: Theory, Practice, and Visualization (2nd ed.). Wiley, 2015.
[18] Sen, A. (1976). Poverty: An ordinal approach to measurement. Econometrica, 44(2), 219-231, 1976.
[19] Sheather, S. J., & Jones, M. C. (1991). A reliable data-based bandwidth selection method for kernel density estimation. Journal of the Royal Statistical Society: Series B, 53(3), 683-690, 1991.
[20] Silverman, B. W. (1986). Density Estimation for Statistics and Data Analysis. Chapman & Hall, London, 1986.
[21] Simonoff, J. S. (1996). Smoothing Methods in Statistics. Springer, New York, 1996.
[22] Wand, M. P. & Jones, M. C. (1995) Kernel Smoothing. Chapman and Hall Ltd., London, 1995.
[23] Y. Ciss, G. Dia, A. Diakhaby. Bidimensional non-parametric estimation of well-being distribution and poverty index. Afrika Statistika, Vol. 9, 2014, pages 695-725.
[24] Youssou Ciss; Galaye Dia; Aboubakary Diakhaby. Non-parametric estimation of income distribution and poverty index in the unidimensional context with $alphain [0,1]$. C. R.Acad.Sci.Paris, Ser. I 353 (2015) no. 10, pp. 947-952.
[25] Z. Baradine and Y. Ciss and A. Diakhaby. Adaptive kernel density estimation of income distribution and poverty index. In A Collection of Papers in Mathematics and Related Sciences, a festschrift in honour of the late Galaye Dia (Editors : Seydi H., Lo G.S. and Diakhaby A.). Spas Editions, Euclid Series Book, pp. 103 - 128.
Cite This Article
  • APA Style

    Ciss, Y., Sinclair, M. D., Bangoura, M. D., Diakhaby, A. (2026). Bivariate Radialsymmetric Kernel Density Estimation of Well-being Distribution and Poverty Index. American Journal of Theoretical and Applied Statistics, 15(5), 177-201. https://doi.org/10.11648/j.ajtas.20261505.11

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    ACS Style

    Ciss, Y.; Sinclair, M. D.; Bangoura, M. D.; Diakhaby, A. Bivariate Radialsymmetric Kernel Density Estimation of Well-being Distribution and Poverty Index. Am. J. Theor. Appl. Stat. 2026, 15(5), 177-201. doi: 10.11648/j.ajtas.20261505.11

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    AMA Style

    Ciss Y, Sinclair MD, Bangoura MD, Diakhaby A. Bivariate Radialsymmetric Kernel Density Estimation of Well-being Distribution and Poverty Index. Am J Theor Appl Stat. 2026;15(5):177-201. doi: 10.11648/j.ajtas.20261505.11

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  • @article{10.11648/j.ajtas.20261505.11,
      author = {Youssou Ciss and Mamadou Djitan Sinclair and Mohamed Dinah Bangoura and Aboubakary Diakhaby},
      title = {Bivariate Radialsymmetric Kernel Density Estimation of Well-being Distribution and Poverty Index},
      journal = {American Journal of Theoretical and Applied Statistics},
      volume = {15},
      number = {5},
      pages = {177-201},
      doi = {10.11648/j.ajtas.20261505.11},
      url = {https://doi.org/10.11648/j.ajtas.20261505.11},
      eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajtas.20261505.11},
      abstract = {In two previous papers, we proposed two bivariate product kernel estimators for the bi-dimensional extension of the Foster, Greer and Thorbecke (FGT) index  based respectively on classical and adaptive kernel. The Foster, Greer and Thorbecke (FGT) index was introduced in the literature for the purpose of a dominance approach to multidimensional poverty. The poverty measure utilized in this dominance method is fundamentally a generalization, from one to two dimensions, of this Foster, Greer and Thorbecke index with separate poverty aversion parameters for each dimension. This statistical method (the product kernel estimator) has the following main disadvantes: the curse of dimensionality, the complex selection of the bandwidth, and high computational costs.  In this  study, we focus on a bivariate radialsymmetric kernel estimator for the bi-dimensional extension of the Foster, Greer and Thorbecke index. Our new bivariate kernel estimator is developed with a classical bivariate kernel of Parzen-Rosenblatt of a probability density function (pdf) utilizing Riemann sums. We next provide complete asymptotic  behaviour by establishing both almost-sure uniform and  uniform mean square consistencies for the bivariate radialsymmetric kernel estimator. A simulation study indicates that the proposed bivariate kernel estimator performs favorably for small samples comparatively to the bivariate multiplicative kernel estimator.},
     year = {2026}
    }
    

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  • TY  - JOUR
    T1  - Bivariate Radialsymmetric Kernel Density Estimation of Well-being Distribution and Poverty Index
    AU  - Youssou Ciss
    AU  - Mamadou Djitan Sinclair
    AU  - Mohamed Dinah Bangoura
    AU  - Aboubakary Diakhaby
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    N1  - https://doi.org/10.11648/j.ajtas.20261505.11
    DO  - 10.11648/j.ajtas.20261505.11
    T2  - American Journal of Theoretical and Applied Statistics
    JF  - American Journal of Theoretical and Applied Statistics
    JO  - American Journal of Theoretical and Applied Statistics
    SP  - 177
    EP  - 201
    PB  - Science Publishing Group
    SN  - 2326-9006
    UR  - https://doi.org/10.11648/j.ajtas.20261505.11
    AB  - In two previous papers, we proposed two bivariate product kernel estimators for the bi-dimensional extension of the Foster, Greer and Thorbecke (FGT) index  based respectively on classical and adaptive kernel. The Foster, Greer and Thorbecke (FGT) index was introduced in the literature for the purpose of a dominance approach to multidimensional poverty. The poverty measure utilized in this dominance method is fundamentally a generalization, from one to two dimensions, of this Foster, Greer and Thorbecke index with separate poverty aversion parameters for each dimension. This statistical method (the product kernel estimator) has the following main disadvantes: the curse of dimensionality, the complex selection of the bandwidth, and high computational costs.  In this  study, we focus on a bivariate radialsymmetric kernel estimator for the bi-dimensional extension of the Foster, Greer and Thorbecke index. Our new bivariate kernel estimator is developed with a classical bivariate kernel of Parzen-Rosenblatt of a probability density function (pdf) utilizing Riemann sums. We next provide complete asymptotic  behaviour by establishing both almost-sure uniform and  uniform mean square consistencies for the bivariate radialsymmetric kernel estimator. A simulation study indicates that the proposed bivariate kernel estimator performs favorably for small samples comparatively to the bivariate multiplicative kernel estimator.
    VL  - 15
    IS  - 5
    ER  - 

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Author Information
  • West African Institute of Mathematics, Gamal Abdel Nasser University, Conakry, Guinea

  • West African Institute of Mathematics, Gamal Abdel Nasser University, Conakry, Guinea

  • Department of Mathematics, Gamal Abdel Nasser University, Conakry, Guinea

  • West African Institute of Mathematics, Gamal Abdel Nasser University, Conakry, Guinea

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