Skip to main content
Research article - Peer-reviewed, 2012

Bridging National and Reference Definitions for Harmonizing Forest Statistics

Ståhl, Göran; Cienciala, Emil; Chirici, Gherardo; Lanz, Adrian; Vidal, Claude; McRoberts, Ronald E.; Winter, Susanne; Rondeux, Jacques; Schadauer, Klemens; Tomppo, Erkki


Harmonization is the process of making information and estimates comparable across administrative borders. The degree to which harmonization succeeds depends on many factors, including the conciseness of the definitions, the availability and quality of data, and the methods used to convert an estimate according to a local definition to an estimate according to the reference definition. Harmonization requires the availability and use of common reference definitions and methods for converting from estimates based on national definitions to estimates based on reference definitions. This article focuses on conversion methods, which are characterized as "bridges" because they can be seen as a means of crossing from islands of local definitions to the mainland of a reference definition. A structured approach is proposed for constructing bridges of three kinds: reductive, neutral, and expansive bridges. A hierarchical decision tree is presented to guide users and to summarize the propositions and case examples with different types of bridges to illustrate the concepts. Although the article addresses harmonization of forest information, the results are relevant for harmonizing a broad variety of area statistics. FOR. SCI. 58(3):214-223.


forest resource assessment; statistics; harmonization; national forest inventory; standardization

Published in

Forest Science
2012, volume: 58, number: 3, pages: 214-223

Authors' information

Swedish University of Agricultural Sciences, Department of Forest Resource Management
Cienciala, Emil
Institute of Forest Ecosystem Research
Chirici, Gherardo
University of Molise
Lanz, Adrian
Swiss Federal Institute for Forest, Snow and Landscape Research (WSL)
Vidal, Claude
Inventaire forestier national
McRoberts, Ronald E.
US Forest Service
Winter, Susanne
Technical University of Munich (TUM)
Rondeux, Jacques
University of Liège
Schadauer, Klemens
Austrian Research Centre for Forests (BFW)
Tomppo, Erkki
Finnish Forest Research Institute (Metla)

UKÄ Subject classification

Forest Science
Probability Theory and Statistics

Publication Identifiers


URI (permanent link to this page)