Full text of this article is only available in PDF format.

Jouni Siipilehto (email), Sakari Sarkkola, Lauri Mehtätalo

Comparing regression estimation techniques when predicting diameter distributions of Scots pine on drained peatlands

Siipilehto J., Sarkkola S., Mehtätalo L. (2007). Comparing regression estimation techniques when predicting diameter distributions of Scots pine on drained peatlands. Silva Fennica vol. 41 no. 2 article id 300. https://doi.org/10.14214/sf.300


We compared different statistical methods for fitting linear regression models to a longitudinal data of breast height diameter (dbh) distributions of Scots pine dominated stands on drained peatlands. The parameter prediction methods for two parameters of Johnson’s SB distribution, fitted to basal-area dbh distributions, were: 1) a linear model estimated by ordinary least squares (OLS), 2) a multivariate linear model estimated using the seemingly unrelated regression approach (SUR), 3) a linear mixed-effects model with random intercept (MIX), and 4) a multivariate mixed-effects model (MSUR). The aim was to clarify the effect of taking into account the hierarchy of the data, as well as simultaneous estimation of the correlated dependent variables on the model fit and predictions. Instead of the reliability of the predicted parameters, we focused on the reliability of the models in predicting stand conditions. Predicted distributions were validated in terms of bias, RMSE, and error deviation in the generated quantities of the growing stock. The study material consisted of 112 successively measured stands from 12 experimental areas covering the whole of Finland (total of 608 observations). Two independent test data sets were used for model validation. All the advanced regression techniques were superior to OLS, when exactly the same independent stand variables were included. SUR and MSUR were ranked the overall best and second best, respectively. Their ranking was the same in the modeling data, whereas MSUR was superior in the peatland test data and SUR in the mineral soil test data. The ranking of the models was logical, but may not be widely generalized. The SUR and MSUR models were considered to be relevant tools for practical forest management planning purposes over a variety of site types and stand structures.

Pinus sylvestris; drained peatland; dbh distribution; Johnson’s SB function; regression estimation methods

Author Info
  • Siipilehto, Finnish Forest Research Institute, Vantaa Research Unit, P.O. Box 18, FI-01301 Vantaa, Finland E-mail jouni.siipilehto@metla.fi (email)
  • Sarkkola, Finnish Forest Research Institute, Vantaa Research Unit, P.O. Box 18, FI-01301 Vantaa, Finland E-mail ss@nn.fi
  • Mehtätalo, University of Joensuu, Faculty of Forestry, P.O. Box 111, 80101 Joensuu, Finland E-mail lm@nn.fi

Received 7 June 2006 Accepted 8 February 2007 Published 31 December 2007

Views 2286

Available at https://doi.org/10.14214/sf.300 | Download PDF

Creative Commons License CC BY-SA 4.0

Click this link to register to Silva Fennica.
Log in
If you are a registered user, log in to save your selected articles for later access.
Contents alert
Sign up to receive alerts of new content

Your selected articles
Your search results
Maltamo M., (1997) Comparing basal area diameter distributions esti.. Silva Fennica vol. 31 no. 1 article id 5609
Kilkki P., Päivinen R. (1986) Weibull function in the estimation of the basal .. Silva Fennica vol. 20 no. 2 article id 5270
Kapustinskaité T., (1975) Ash content of peatland soils and stand growth i.. Silva Fennica vol. 9 no. 3 article id 4924
Päivänen J., (1973) The effect of thinning on the snow cover and soi.. Silva Fennica vol. 7 no. 2 article id 4881
Erjala P., Saramäki J. (1972) Determination of the need for fertilizer applica.. Silva Fennica vol. 6 no. 1 article id 4860
Seppälä K., (1971) The quantity of fertilizer and application metho.. Silva Fennica vol. 5 no. 2 article id 4838
Heikurainen L., Ouni J. (1970) Height growth of seedling stands growing on peat.. Silva Fennica vol. 4 no. 2 article id 4817
Päivänen J., (1974) Nutrient removal from Scots pine canopy on drain.. Acta Forestalia Fennica vol. 0 no. 139 article id 7573
Seppälä K., (1969) Post-drainage growth rate of Norway spruce and S.. Acta Forestalia Fennica vol. 0 no. 93 article id 7611
Repola J., Hökkä H. et al. (2018) Models for diameter and height growth of Scots p.. Silva Fennica vol. 52 no. 5 article id 10055
Moilanen M., Hytönen J. et al. (2015) Fertilization increased growth of Scots pine and.. Silva Fennica vol. 49 no. 3 article id 1301