Environmental and Ecological Statistics

, Volume 12, Issue 2, pp 139–154 | Cite as

Design unbiased estimation in line intersect sampling using segmented transects

  • David L.R. Affleck
  • Timothy G. Gregoire
  • Harry T. Valentine


In many applications of line intersect sampling, transects consist of multiple, connected segments in a prescribed configuration. The relationship between the transect configuration and the selection probability of a population element is illustrated and a consistent sampling protocol, applicable to populations composed of arbitrarily shaped elements, is proposed. It is shown that this protocol obviates the arbitrary practice of treating multiple intersections of a single particle as independent probabilistic events and preserves the design-unbiasedness of Kaiser’s (1983, Biometrics 39, 965–976) conditional and unconditional estimators, suitably generalized to segmented transect designs. The relative efficiency and utility of segmented transect designs are also discussed from a fixed population perspective.


coarse woody debris design-unbiasedness multiple intersections transect configuration 


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  1. Barabesi, L., Fattorini, L. 1998The use of replicated plot, line and point sampling for estimating species abundance and ecological diversityEnvironmental and Ecological Statistics535370CrossRefGoogle Scholar
  2. Canfield, R.H. 1941Application of the line interception method in sampling range vegetationJournal of Forestry3938894Google Scholar
  3. Cassel, C.M., Särndal, C.E., Wretman, J.H. 1977Foundations of Inference in Survey SamplingWileyNew YorkGoogle Scholar
  4. Delisle, G.P., Woodward, P.M., Titus, S.J., Johnson, A.F. 1988Sample size and variability of fuel weight estimates in natural stands of lodgepole pineCanadian Journal of Forest Research1864952Google Scholar
  5. DeVries, P.G. (1973) A general theory on line intersect sampling with application to logging residue inventory. Mededelingen Landbouwhogeschool 73-11, Wageningen, The NetherlandsGoogle Scholar
  6. DeVries, P.G. 1979Line intersect sampling statistical theory, applications, and suggestions for extended use in ecological inventoryCormack, R.Patil, G.Robson, D. eds. Sampling Biological PopulationsInternational Co-operative Publishing HouseFairland, MD170Google Scholar
  7. Eberhardt, L.L. 1978Transect methods for population studiesJournal of Wildlife Management42131Google Scholar
  8. Gregoire, T.G. 1982The unbiasedness of the mirage correction procedure for boundary overlapForest Science285048Google Scholar
  9. Gregoire, T.G., Monkevich, N.S. 1994The reflection method of line intercept sampling to eliminate boundary biasEnvironmental and Ecological Statistics121926CrossRefGoogle Scholar
  10. Gregoire, T.G., Valentine, H.T. 2003Line intersect sampling: Ell-shaped transects and multiple intersectionsEnvironmental and Ecological Statistics1026379CrossRefMathSciNetGoogle Scholar
  11. Kaiser, L. 1983Unbiased estimation in line-intercept samplingBiometrics3996576Google Scholar
  12. Kendall, M.G., Moran, P.A.P. 1963Geometrical ProbabilityHafnerNew YorkGoogle Scholar
  13. Marshall, P.L., Davis G., and LeMay, V.M. (2000) Using line intersect sampling for coarse woody debris. Technical Report TR-003, Research Section, Vancouver Forest Region, B.C. Ministry of ForestsGoogle Scholar
  14. McIntyre, G.A. 1953Estimation of plant density using line transectsJournal of Ecology4132030Google Scholar
  15. McRae, D.J., Alexander, M.E., and Stocks, B.J. (1979) Measurement and description of fuels and fire behavior on prescribed burns: a handbook, Information Report O-X-287, Canadian Forestry Service, Great Lakes Forest Research Centre, Sault Ste. Marie, ON.Google Scholar
  16. O’Brien, R.A. (1989) Comparison of overstory canopy cover estimates on forest survey plots. Research Paper INT-417, USDA Forest Service, Intermountain Research Station, Ogden, UT.Google Scholar
  17. Ringvall, A., Ståhl, G. 1999Field aspects of line intersect sampling for assessing coarse woody debrisForest Ecology and Management11916370CrossRefGoogle Scholar
  18. Runkle, J.R. (1992) Guidelines and sample protocol for sampling forest gaps. General Technical Report PNW-GTR-283, USDA Forest Service, Pacific Northwest Research Station, Portland, OR.Google Scholar
  19. Särndal, C.E., Swensson, B., Wretman, J.H. 1992Model Assisted Survey SamplingSpringer-VerlagNew YorkGoogle Scholar
  20. Stewart, J. 1995Multivariable Calculus3Brooks/ColePacific Grove, CAGoogle Scholar
  21. Valentine, H.T., Gove, J.H., Gregoire, T.G. 2001Monte Carlo approaches to sampling forested tracts with lines or pointsCanadian Journal of Forest Research31141024CrossRefGoogle Scholar
  22. Van Wagner, C.E. 1968The line intersect method in forest fuel samplingForest Science14206Google Scholar
  23. Waddell, K.L. (2002) Sampling coarse woody debris for multiple attributes in extensive resource inventories. Ecological Indicators, 1, 139–153Google Scholar
  24. Warren, W.G., Olsen, P.F. 1964A line intersect technique for assessing logging wasteForest Science1026776Google Scholar

Copyright information

© Springer Science+Business Media, Inc. 2005

Authors and Affiliations

  • David L.R. Affleck
    • 1
  • Timothy G. Gregoire
    • 1
  • Harry T. Valentine
    • 2
  1. 1.School of Forestry and Environmental StudiesYale UniversityNew HavenUSA
  2. 2.USDA Forest ServiceNortheastern Research StationDurhamUSA

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