Improving robust ratio estimation in longitudinal surveys with outlier observations

Authors

  • Roberto Gismondi ISTAT, Istituto Nazionale di Statistica

DOI:

https://doi.org/10.6092/issn.1973-2201/3575

Abstract

The Hulliger’s robust estimation technique consists in the re-weighting of units identified as outliers through a Robustified Ratio Estimator (RRE), according to which outliers contribute to the final estimate with a sample weight reduced with respect to the original one. Outlier observations are identified through a standardised function founded on the difference between observed and expected values. A crucial aspect concerns the choice of the acceptation threshold, which plays a role in the re-weighting process as well. In this context, we propose some potential improvements of the RRE, concerning the use of an objective criterion for fixing the threshold and the re-weighting rules. Results of two empirical attempts based on real data derived from longitudinal surveys show that, in the most part of case studies, the proposed changes contribute to improve efficiency of estimates with respect to the ordinary ratio estimator.

References

AA.VV. (2008a), “Seminario: strategie e metodi per il controllo e la correzione dei dati nelle indagini strutturali sulle imprese: alcune esperienze nel settore delle statistiche strutturali”, Contributi Istat, 7/2008, Istat, Roma.

AA.VV. (2008b), “Seminario: strategie e metodi per il controllo e la correzione dei dati nelle indagini congiunturali sulle imprese: alcune esperienze nel settore delle statistiche congiunturali”, Contributi Istat, 13/2008, Istat, Roma.

J.F. BEAUMONT, A. ALAVI (2004), “Robust Generalized Regression Estimation”, Survey Methodology, Vol.30, 2, pp. 195-208.

R.L. CHAMBERS (1986), “Outlier Robust Finite Population Estimation”, Journal of the American Statistical Association, 81, pp. 1063-1069.

R.L. CHAMBERS, P. KOKIC, P. SMITH, M. CRUDDAS (2000), “Winsorization for Identifying and Treating Outliers in Business Surveys”, Proceedings of the Second International Conference on Establishment Surveys, pp. 717-726, American Statistical Association, Alexandria, Virginia.

G. CICCHITELLI, A. HERZEL, G.E. MONTANARI (1992), Il campionamento statistico. Il Mulino, Bologna.

C. CROUX, P.J. ROUSSEEUW, O. HÖSSJER (1994), “Generalised S-Estimators”, Journal of the American Statistical Association, Vol. 89, N. 428, pp. 1271-1281.

M.R. ELLIOTT, R.J.A. LITTLE (2000), “Model-Based Alternatives to Trimming Survey Weights”, Journal of Official Statistics, 16, pp. 191-209.

R. GISMONDI (2002), “Confronti tra metodi per l’identificazione di osservazioni anomale in indagini longitudinali: proposte teoriche e verifiche empiriche”, Rivista di Statistica Ufficiale, 1, pp. 25-60, Franco Angeli, Milano.

R. GISMONDI, A.R. GIORGI, T. PICHIORRI (2009), “The Hulliger’s Criterion for Managing Outliers: New Proposals and Application to Retail Trade Turnover”, Atti della riunione scientifica SIS: “Analysis of large data-sets”, Pescara, 23-25 settembre 2009, pp. 435-438, CLEUP, Padova.

J.P. GWET, H. LEE (2000), “An Evaluation of Outlier-Resistant Procedures in Establishment Surveys”, Proceedings of the Second International Conference on Establishment Surveys, pp. 707- 716, American Statistical Association, Alexandria, Virginia.

J.P. GWET, L.P. RIVEST (1992), “Outlier Resistant Alternatives to the Ratio Estimator”, Journal of the American Statistical Association, Vol. 87, 420, pp. 1174-1182.

B. HULLIGER (1995), “Outlier Robust Horvitz-Thompson Estimators”, Survey Methodology, Vol. 21, 1, pp. 79-87.

B. HULLIGER (1999), “Simple and Robust Estimators for Sampling”, Proceedings of the Section on Survey Research Methods, American Statistical Association, pp. 54-63.

ISTAT, CBS, SFSO, EUROSTAT (2007), Recommended Practices for Editing and Imputation in Cross- Sectional Business Surveys, available on: www.edimbus.istat.it.

P.N. KOKIC, P.A. BELL (1994), “Optimal Winsorizing Cutoffs for a Stratified Finite Population Estimator”, Journal of Official Statistics, 10, pp. 419-435.

M. LATOUCHE, J.M. BERTHELOT (1992), “Use of a Score Function to Prioritize and Limit Recontacts in Editing Business Surveys”, Journal of Official Statistics, 8, pp. 389-400.

H. LEE (1991), “Model-Based Estimators That Are Robust to Outliers”, Proceedings of the 1991 Annual Research Conference, Bureau of the Census, pp. 178-202, Washington DC, U.S. Department of Commerce.

S. LUNDSTRÖM, C.E. SÄRNDAL (1999), “Calibration as a Standard Method for Treatment of Nonresponse”, Journal of Official Statistics, Vol. 15, 2, pp. 305-327.

J.N.K. RAO (1985), “Conditional Inferences in Survey Sampling”, Survey Methodology, 11, pp. 15-31.

R. REN, R. CHAMBERS (2002), “Outlier Robust Imputation of Survey Data via Reverse Calibration”, Southampton Statistical Sciences Research Institute Working Paper M03/19, available on http://eprints.soton.ac.uk/8169/01/s3ri-workingpaper-m03-19.pdf.

C.E. SÄRNDAL, B. SWENSSON, J. WRETMAN (1993), Model Assisted Survey Sampling, Springer Verlag.

D.T. SEARLS (1966), “An Estimator for a Population Mean Which Reduces the Effect of Large True Observations”, Journal of the American Statistical Association, 61, pp. 1200-1204.

V. TODOROV, M. TEMPL, P. FILZMOSER (2009), “Outlier Detection in Survey Data using Robust Methods”, paper presented at the UN Work Session on Statistical Data Editing, October 5-7, Neuchâtel, Switzerland.

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Published

2010-03-31

How to Cite

Gismondi, R. (2010). Improving robust ratio estimation in longitudinal surveys with outlier observations. Statistica, 70(1), 23–39. https://doi.org/10.6092/issn.1973-2201/3575

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