Volume 63 | Number 1 | Year 2018 | Article Id. IJMTT-V63P502 | DOI : https://doi.org/10.14445/22315373/IJMTT-V63P502
While doing statistical analysis, a problem often resists that there may exist some extremely small or large observation (outliers). To deal with such problem diagnostics of the observations is the best option for the model building process. Mostly analysts use ordinary least square (OLS) method which is utterly failing in the identification of outliers. In this paper, we use the diagnostics method to detect outliers and influential points in models for count data. Gauss-Newton and Likelihood Distance method approach has been treated to detect the outliers in parameter estimation in non-linear regression analysis. We used these techniques to analyze the performance of residual and influence in the non-linear regression model. The results show us detection of single and multiple outlier cases in count data.
[1] C.R.D and Presscot, "Approximation significance levels for detecting outlier in linear regression," Technometrics, vol. 23, pp. 59-64, 1981.
[2] Hausman, J.A., B. Hall and Z. Griliches, "Econometric Models for Count Data with an Application to the Patents-R and D Relationship," Econometrica , vol. 52, pp. 909-938, 1984.
[3] Nelder, J.A and R. Wedderburn, "Generalized Linear Models," Journal of the Royal Statistical Society A, vol. 135, pp. 370-384, 1972.
[4] Mullahy and J, "Specification and Testing of some modified count data models," Journal of Econometrics, vol. 33, pp. 341-365, 1986.
[5] Cameron, A.C and P. Trivedi, "Count Data Models for Financial Data" in G.S Maddala and C.R. Rao, eds., Handbook of Statistics, vol. 14, North-Holland: Statistical Methods in Finance, Amsterdam,, 1996.
[6] M. Ali, Z. Ali and A. Choo, "Diagnostics of Single and Multiple outliers on likelihood distance," AJER, vol. 07, pp. 352-357, 2018.
[7] McCullagh, p. and J. Nelder, Generalized Linear Models, edition 1 and 2, Lodon: Chapman and Hall, 1983, 1989.
[8] Cameron, A.C and P. Trivedi, "Economics Models Based on Count Data; Comparison and Application of Some Estimators," Journal of Applied Econometrics, vol. 01, pp. 29-53, 1986.
[9] Ronning, G, R. Jung and i. L. e. al., "Estimation of a First Order Autoregressive Process with Poisson Marginals for Count Data," in Advances in GLIM and Statistical Modelling, New York, Springer Verlag, 1972, pp. 188-194.
[10] C.R.D and J.Amer, "Influence observations in linear regression," Statist Associates, vol. 74, pp. 169-174, 1979.
[11] V. Dujin, M.A.J. and U.B., "Mixture Models for the Analysis of Repeated Count Data," Journal of the Royal Statistical Society C, vol. 44, pp. 473-485, 1995.
[12] Williams and D.A., "Generalized Linear Model Diagnostics Using the Deviance and Single Case Deletions," Applied Statistics, vol. 36, pp. 181-191, 1987.
[13] L. Vanegas, L. Rondin and F. Cysneiros, "Diagnostic procedures in Birnbaum Saunders nonliear regression models," Computational Statistics and Data Analysis, vol. 56, pp. 1662-1680, 2012.
Zamir Ali, Yu Feng, Ali Choo, Munsir Ali, "Statistical Diagnostics of Models for Count Data," International Journal of Mathematics Trends and Technology (IJMTT), vol. 63, no. 1, pp. 9-15, 2018. Crossref, https://doi.org/10.14445/22315373/IJMTT-V63P502