Abstract
The goal of this paper is to investigate the question of the importance of aggregation of the Paasche and Laspeyres versions of the Malmquist quantity and productivity indexes from both theoretical and empirical perspectives. We discuss the existing justification and provide an alternative theoretical justification based on results from the functional equations literature. We also use real data (from Kumar and Russell (2002, American Economic Review)) to illustrate how dramatic the differences in conclusions can be in practice, depending on whether one employs Laspeyres or Paasche productivity indexes.
Similar content being viewed by others
Notes
For a nice exposition of the history of index numbers, see Balk (2008, Chapter 1).
While the roots of this index can be found in Caves et al. (1982a, 1982b), Diewert (1992, p. 240) appears to be the first who explicitly introduced it after apparently being inspired by the geometric descriptions from Moorsteen (1961, p. 460) and the intuitive description of Hicks (1961, footnote 4). He dubbed it as the “Hicks–Moorsteen approach to productivity indexes” and then it often emerged as the “Hicks–Moorsteen Productivity index” or the “Hicks–Moorsteen TFP index” or simply the “Hicks–Moorsteen index” in various works. About the same time, Bjurek (1996) developed this index more explicitly and generalized it to allow for technical inefficiency and called it the “Malmquist TFP index”, although others started to call it the “Bjurek productivity index” or the “Bjurek TFP index” (or simply the “Bjurek index”). Professor Bert Balk suggested to us that the name of Hicks should not be there, referring to it as the “Moorsteen-Bjurek productivity index”, although see explanations in Diewert and Fox (2017, p. 276) on the justification of the influence from Hicks. Meanwhile, Sickles and Zelenyuk (2019, p. 110) suggested that the name of Diewert (since he was the first to suggest this index explicitly), should be also added there, and also the name of Malmquist, since it is defined as the ratio of Malmquist indexes. Finally, the name of Shephard can also be justified, since his distance functions were used to define this index explicitly.
We thank an anonymous referee for inspiring this discussion.
It appears that Westergaard (1890) was the first to discuss this requirement for indexes, later considered by Fisher (1911) under the name of ‘test by changing base’ and later, in Fisher (1922, p. 270), under the name of ‘circular test’. Also see related discussions and many references in Balk and Althin (1996), 2004 CPI Manual and Sickles and Zelenyuk (2019), who we follow here.
Similarly to the CPI manual, we prefer using the term circularity or ‘circular test’, because the term “transitivity” is a somewhat unfortunate name here due to confusion with the more general (and widely accepted) transitivity property of relations in mathematics and in consumer theory of economics (see Sickles and Zelenyuk (2019) for further discussions).
Essentially the same result was much earlier derived in a somewhat overlooked paper of Konüs and Byushgens (1926).
Also, see Diewert and Fox (2017) for related discussions on the caveats of fixed-weight indexes.
Also see Balk (2008), Theorem 3.11, p. 97 and the related discussion.
Also note that similar reasoning applies for the additive measures, sometimes referred to as indicators, as outlined in Färe and Zelenyuk (2019). In fact, their result was derived after the result of this section, although published earlier.
We thank Robert G. Chambers for pointing this out.
We thank an anonymous referee for inspiring this discussion.
This is in fact also the very first data set we tried for our illustration. We also tried newer versions of Penn World Tables and also with more sophisticated measurement of inputs, e.g., by accounting for human capital as in Henderson and Russell (2005) or/and financial capital as in Badunenko and Romero-Avila (2013), as well as tried micro data (on farmers) and these data sets generally confirmed the main conclusions we discussed here. Also, for somewhat related evidence in different contexts, see Balk (2008, Chapter 3) who used artificial data for the contexts of price indexes and Balk and Zofio (2018) for the context of comparing various decompositions of productivity indexes for banking data.
Their estimates of the MPI can be recovered from their estimates of efficiency change and technology change.
Other popular methods include Stochastic Frontier Analysis or SFA (parametric, semi-parametric and non-parametric) and their symbiosis, such as Stochastic DEA, etc. See Kumbhakar and Lovell (2002) and Sickles and Zelenyuk (2019) for a comprehensive textbook style discussion and references therein for more details.
All estimations were done in Matlab by the authors and then independently checked in R by one of our research assistants. For Matlab, we adapted some DEA codes from Leopold Simar, while for R we used the “Benchmarking” package of Bogetoft and Otto (https://cran.r-project.org/web/packages/Benchmarking/Benchmarking.pdf) and ‘deaR’ package of Coll-Serrano, Bolos and Suarez (https://cran.r-project.org/web/packages/deaR/deaR.pdf).
In this case, the input and output oriented Shephard’s distance functions are reciprocal to each other in general and for DEA in particular, i.e., \({\widehat{D}}_{i}^{\tau }({y}^{tj},{x}^{sj})={({\widehat{D}}_{o}^{\tau }({x}^{sj},{y}^{tj}))}^{-1}\) (e.g., see Färe and Lovell (1978)).
E.g., see Simar and Wilson (2015) for a comprehensive review of the statistical aspects of these estimators and references therein.
It is also possible to consider the so-called Free Disposal Hull (FDH) approach, which only imposes free disposability of inputs and outputs, by requiring \({\mathcal{Z}}=\{({z}^{1},...,{z}^{n})\,:\,{z}^{k}\in \{0,1\},\,k=1,...,n;\,\mathop{\sum }\nolimits_{k = 1}^{n}{z}^{k}=1\}\), which is somewhat an outsider in the literature, partly because it has an even slower rate of convergence, Op(n−1/(N+M)), and often suffers from the overfitting problem and low discriminative power in relatively small samples so we do not pursue it here.
As is well-known, the DEA may give infeasible solutions for MPI under non-CRS assumptions. In our data, this happened only for six countries (with relatively small GDP) and only for DEA-VRS where the implosion of technology was allowed (The cases with infeasible solutions are indicated with the original Matlab output for them, containing “Inf” or “Infi”.).
See related discussions in Keynes (1930) and Balk (2008, p. 28–30).
Indeed, the gap between LPI and MPI is fully explained by the contributions from the other inputs: e.g., in the data set we used in Section 6, it can be explained by the capital-deepening contribution (Kumar and Russell (2002)), while in Henderson and Russell (2005) data set it can be explained by physical and human capital deepening.
Here, the assumption of CRS shall not be dogmatically understood as a belief that the ‘true’ technology is CRS, rather than as a selection of a relevant common benchmark/reference, e.g., coherent with the socially optimal scale and the notion of maximal average productivity.
We thank an anonymous referee for inspiring this discussion.
References
Aczél J (1987) A short course on functional equations: based upon recent applications to the social and behavioral sciences. Theory and decision library: Mathematical and statistical methods, D. Reidel
Aczél J (1990) Determining merged relative scores. J Math Anal Appl 150:20–40
Badunenko O, Romero-Avila D (2013) Financial development and the sources of growth and convergence. Int Econ Rev 54:629–663
Balk B, Färe R, Grosskopf S (2003) The theory of economic price and quantity indicators. Econ Theory 23:149–164
Balk B, Zofio J (2018) The many decompositions of total factor productivity change. ERIM Report Series Research in Management ERS-2018-003-LIS.
Balk BM (1998) Industrial price, quantity, and productivity indices: the micro-economic theory and an application. Kluwer Academic Publishers, Boston, MA
Balk BM (2008) Price and quantity index numbers: models for measuring aggregate change and difference. Cambridge University Press, New York, NY
Balk BM, Althin R (1996) A new, transitive productivity index. J Prod Anal 7:19–27
Bjurek H (1996) The Malmquist total factor productivity index. Scand J Econ 98:303–313
Caves DW, Christensen LR, Diewert WE (1982a) The economic theory of index numbers and the measurement of input, output, and productivity. Econometrica 50:1393–1414
Caves DW, Christensen LR, Diewert WE (1982b) Multilateral comparisons of output, input, and productivity using superlative index numbers. Econ J 92:73–86
Chambers RG (1988) Applied production analysis: a dual approach. Cambridge University Press, New York, NY
Chambers RG, Färe R (1994) Hicks neutrality and trade biased growth: a taxonomy. J Econ Theory 64:554–567
Diewert WE (1980) Capital and the theory of productivity measurement. Am Econ Rev 70:260–267
Diewert WE (1992) Fisher ideal output, input, and productivity indexes revisited. J Prod Anal 3:211–248
Diewert WE, Fox KJ (2017) Decomposing productivity indexes into explanatory factors. Eur J Oper Res 256:275–291
Diewert WE (1993) Nakamura, A.O. (Eds.) Essays in index number theory. volume 1. Amsterdam, NL:Elsevier.
Eichhorn W (1976) Fisher’s tests revisited. Econometrica 44:247–256
Eichhorn W (1978) Functional equations in economics. Reading, MA:Addison-Wesley Pub. Co., Advanced Book Program. Includes indexes
Eltetö O, Köves P (1964) On a problem of index number computation relating to international comparison. Statisztikai Szemle 42:507–518
Färe R, Grosskopf S (1996) Intertemporal production frontiers: with dynamic DEA. Kluwer Academic Publishers, Norwell, MA
Färe R, Grosskopf S, Roos P (1996) On two definitions of productivity. Econ Lett 53:269–274
Färe R, Lovell CK (1978) Measuring the technical efficiency of production. J Econ Theory 19:150–162
Färe R, Mizobuchi H, Zelenyuk V (2020) Hicks neutrality and homotheticity in technologies with multiple inputs and multiple outputs. Omega, forthcoming. https://doi.org/10.1016/j.omega.2020.102240
Färe R, Primont D (1995) Multi-output production and duality: theory and applications. Kluwer Academic Publishers, New York, NY
Färe R, Zelenyuk V (2005) On Farrell’s decomposition and aggregation. Int J Bus Econ 4:167–171
Färe R, Zelenyuk V (2019) On Luenberger input, output and productivity indicators. Econ Lett 179:72 – 74
Fisher I (1911) The purchasing power of money. Macmillan, New York, NY
Fisher I (1921) The best form of index number. J Am Stat Assoc 17:533–537
Fisher I (1922) The making of index numbers. Houghton Mifflin, Boston, MA
Funke H, Hacker G, Voeller J (1979) Fisher’s circular test reconsidered. Swiss J Econ Stat 115:677–688
Funke H, Voeller J (1978) A note on the characterization of Fisher’s “ideal index”, in: Eichhorn, W., Henn, R., Opitz, O., Shephard, R.W. (Eds.), Theory and applications of economic indices. Heidelberg, DE: Physica-Verlag, pp. 177-181.
Gini C (1931) On the circular test of index numbers. Metron 9:3–24
Henderson DJ, Russell RR (2005) Human capital and convergence: a production-frontier approach. Int Econ Rev 46:1167–1205
Hicks JR (1961) Measurement of capital in relation to the measurement of other economic aggregates, in: Hague, D.C. (Ed.), Theory of Capital. New York, NY: Springer.
Keynes J (1930) A Treatise on Money. Number v. 1 in A Treatise on Money, Harcourt, Brace.
Konüs AA (1939) The problem of the true index of the cost of living. Econometrica 7, 10-29. Translated into English and published in 1939.
Konüs AA, Byushgens SS (1926) K probleme pokupatelnoi sily deneg. Voprosy Konyunktury 2:151–172
Kumar S, Russell RR (2002) Technological change, technological catch-up, and capital deepening: relative contributions to growth and convergence. Am Econ Rev 92:527–548
Kumbhakar SC, Lovell CAK (2002) Stochastic frontier analysis. Cambridge University Press, Cambridge UK
Mayer A, Zelenyuk V (2014) An aggregation paradigm for Hicks-Moorsteen productivity indexes. CEPA Working Paper No. WP01/2014.
Mizobuchi H (2017) Productivity indexes under Hicks neutral technical change. J Prod Anal 48:63–68
Moorsteen RH (1961) On measuring productive potential and relative efficiency. Q J Econ 75:151–167
Park BU, Simar L, Zelenyuk V (2008) Local likelihood estimation of truncated regression and its partial derivatives: theory and application. J Econom 146:185–198
Peyrache A (2013) Multilateral productivity comparisons and homotheticity. J Prod Anal 40:57–65
Samuelson P, Swamy S (1974) Invariant economic index numbers and canonical duality: Survey and synthesis. Am Econ Rev 64:566–593
Sickles R, Zelenyuk V (2019) Measurement of productivity and efficiency: theory and practice. Cambridge University Press, New York, NY
Simar L, Wilson PW (2015) Statistical approaches for nonparametric frontier models: a guided tour. Int Stat Rev 83:77–110
Summers R, Heston A (1991) The Penn World Table (Mark 5): an expanded set of international comparisons, 1950-1988. Q J Econ 106:327–368
Szulc B (1964) Indices for multiregional comparisons. Przeglad Statystyczny 3:239–254
Westergaard H (1890) Die GrundzuÍge der Theorie der Statistik. Gustav, Jena
Acknowledgements
The authors thank Robert G. Chambers, Bert Balk, Erwin Diewert, Kevin Fox, Chris Parmeter and Robin Sickles, as well as Duc Manh Pham, Bao Hoang Nguyen, Hong Ngoc Nguyen, Evelyn Smart, Zhichao Wang and all others who gave feedback to various versions of this paper. The authors also acknowledge the financial support from ARC grant (FT170100401) and the overall support from their employers. All views expressed here are those of the authors.
Author information
Authors and Affiliations
Corresponding author
Ethics declarations
Conflict of interest
The authors declare no competing interests.
Additional information
Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Appendix
Appendix
Rights and permissions
About this article
Cite this article
Färe, R., Zelenyuk, V. On aggregation of multi-factor productivity indexes. J Prod Anal 55, 107–133 (2021). https://doi.org/10.1007/s11123-021-00598-w
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11123-021-00598-w