Efficiency analyses often involve panel data which enable to reveal certain longitudinal patterns. However, it is often impossible to maintain the same sample structure when expanding time series. This paper, thus, attempts to test whether there are obvious differences in the trends of efficiency across two different data sets. The research focuses on Lithuanian family farm performance. The data are taken form Farm Accountancy Data Network with different samples covering the periods of 2004-2009 and 2004-2011. The juxtaposition of two-stage efficiency analyses based on different data sets enabled to identify the impact of changes in both the structure of the sample and time series expansion upon the efficiency factors and effects. The analysis suggests that Lithuanian family farms featured generally the same patterns of efficiency during 2004-2011 if opposed to 2004-2009.
Key words: data envelopment analysis, efficiency, family farms, Lithuania.
JEL code: C14, C34, C44, D24, Q12.
Balezentis; T. 2015. The impact of time series expansion in nonparametric analyses of efficiency effects, In Proceedings of the 2015 International Conference “Economic science for rural development”, Jelgava, LLU ESAF, 23-24 April 2015. 37: 35-44. ISSN 1691-3078, ISSN 2255-9930 on line, ISBN 978-9984-48-180-7 [Abstracted / Indexed: ISI Web of Science, AGRIS, CAB Abstracts and EBSCOHost Academic Search Complete databases].
