In spite of theoretical inferiority, a large majority of statistical institutes use non-probabilistic sampling techniques in price surveys. The main disadvantage of non-probabilistic sample design is that the risk of biased results is increased. Attempting to handle this risk in the domain of service producer price indices (SPPI) of professional services, the Croatian Bureau of Statistics (CBS) developed an innovative methodology and implemented it relying on the probability proportional to size (PPS) sample design. The purpose of the paper is to evaluate the impact of the probabilistic sampling strategy on the quality of price indices as shown in the case of SPPI for professional services at the CBS. The paper outlines respective methodological upgrading of SPPI compilation at the CBS, including also the method for variance estimation. The effect of the probabilistic sampling on SPPI is analysed by comparison with traditional purposive sampling surveys. The quality of SPPI based on the probabilistic sample approach is examined by coefficients of variation and confidence intervals.
If the inline PDF is not rendering correctly, you can download the PDF file here.
1. Allen R. G. D (1975). Index Numbers in Theory and Practice. Available at http://ec.europa.eu/eurostat/documents/3859598/6485893/KS-04-14-661-ENN.pdf/f8f5d9d6-50c4-4fa1-9322-c9c00a6377fd [15 March 2018].
2. Croatian Bureau of Statistics (2014). Comparative Studying and Analysing of National and Eurostat Recommended Methodologies for Short Term Statistics – SPPI. Project Technical Assistance of Business Statistics and Upgrading of Data Collection System. Deliverable for project activity 1.2.1 (carried out by GOPA Consultants) Zagreb.
3. Croatian Bureau of Statistics (2015). Methodological Notes on SPPI Production. Project Technical Assistance of Business Statistics and Upgrading of Data Collection System. Deliverable for project activity 1.2.2 (carried out by GOPA Consultants) Zagreb.
4. Croatian Bureau of Statistics (2017). Statistics in Line. Gross Domestic Product Quarterly Gross Value Added constant prices of previous year.
5. Diewert W. E. Nakamura A. O. (1993). Essays in Index Number Theory. Vol. I. Elsevier Science Publishers B.V.
6. European Parliament (1998). Council Regulation (EC) No. 1165/98 concerning short-term statistics. Official Journal No. 162.
7. European Parliament (2005). Regulation (EC) No. 1158/05 of the European Parliament and of the Council of 6 July 2005 amending Council Regulation (EC) No. 1165/98 concerning short-term statistics. Official Journal No. L 191.
8. Eurostat (2010). PEEIs in Focus. A summary for the services producer price index. Available at http://ec.europa.eu/eurostat/documents/3888793/5851641/KS-RA-12-005-EN.PDF [15 March 2018].
9. Eurostat (2012). Chain-linking in STS. Task Force. Final Report. Available at https://ec.europa.eu/eurostat/documents/1916593/1917176/Chain+Linking+Final+Report+2012.pdf/30393337-82e8-4805-8d3b-baaab92b5c6f [30 October 2018].
10. Heravi S. Morgan P. (2014). Sampling Schemes for Price Index Construction: A Performance Comparison across the COICOP Food Groups. Journal of Applied Economics Vol. 46 No 2 pp. 2685-2699.
11. ILO IMF OECD UNECE World Bank (2004a). Consumer Price Index Manual Theory and Practice. Available at http://www.ilo.org/public/english/bureau/stat/guides/cpi/ [15 March 2018].
12. ILO IMF OECD UNECE Eurostat World Bank (2004b). Producer Price Index Manual Theory and Practice. Available at ttps://www.imf.org/external/pubs/ft/ppi/2010/manual/ppi.pdf [15 March 2018].
13. Khemani R. S. Shapiro D. M. (1993) Glossary of Industrial Organisation Economics and Competition Law. OECD.
14. Lothian J. Patak Z. (2007). Enhancing the Quality of Price Indexes – A Sampling Perspective. Available at https://ww2.amstat.org/meetings/ices/2007/proceedings/ICES2007-000224.PDF [20 March 2018].
15. OECD Eurostat (2014). Eurostat-OECD Methodological Guide for Developing Producer Price Indices for Services. OECD Publishing.
16. Reinsdorf M. Triplett J. E. (2009). A Review of Reviews. Ninety Years of Professional Thinking about Consumer Price Index. Available at http://www.nber.org/chapters/c5068 [20 March 2018].
17. Wingren J. E. (2009). Variance analysis for PPI and SPPI. Available at http://www.scb.se/statistik/_publikationer/nr9999_2010a01_br_51_nrft1002.pdf [10 March 2018].
18. Wolter K. M. (1985). Introduction to Variance Estimation. Springer-Verlag New York.