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

Aarne Nyyssönen (email), Pekka Kilkki, Erkki Mikkola

Eräiden metsänarvioimismenetelmien tarkkuudesta

Nyyssönen A., Kilkki P., Mikkola E. (1967). Eräiden metsänarvioimismenetelmien tarkkuudesta. Acta Forestalia Fennica vol. 81 no. 4 article id 7169. https://doi.org/10.14214/aff.7169

English title: On the precision of some methods of forest inventory

Abstract

This paper reports on tests made for the study of alternative methods in forest survey. Data were acquired by measurements in five areas in Finland and in Mexico, varying in size from 20 to 900 ha. The principal characteristics used in the analysis was the entire volume. By the combination of neighbouring plots, the variation could be studied for different plot sizes and survey strips. Variable (relascope) plots could be compared.

A starting point for the comparison of different sampling methods, calculations were made of the coefficients of variation for each plot type; total and within the strata. The amount of decrease of variation with an increasing plot size could be established. Comparisons have been made of the following sampling methods: simple random, stratified random, simple systematic, and stratified systematic sampling.

On comparisons of the standard error of sample mean it was found that in both stratified sampling and different types of systematic sampling there is, with increasing size and diminishing interval of sample plots, an increase in the relative improvement of the result against simple random sampling. Only in exceptional cases did systematic surveys give results which were less precise than those derived by other methods.

In discussion of some methods for determination of the precision of systematic sampling, possibilities of theoretical determination of the degree of precision was considered. An empirical study was made of the behaviour of some equations based on the sample itself. The larger the plot size and the shorter the plot interval, the more the equations overestimated in general the variance of sample mean.

As none of the equations studied gave reliable results, regression equations were calculated for the relative standard error on the basis of the data measured. The independent variables were plot size, plot or strip interval, area of survey unit and mean volume. The results arrived at are based mainly on the complete measurement of one area only. To enable extension of the scope of application, more material is needed with a complete enumeration of trees.

The PDF includes a summary in Finnish.

Keywords
forest inventory; stratified sampling; sampling; methods; sampling methods; systematic sampling; random sampling

Published in 1967

Views 1631

Available at https://doi.org/10.14214/aff.7169 | Download PDF

Creative Commons License CC BY-SA 4.0

Register
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
Nyyssönen A., (1979) International contacts of Finnish forest research Silva Fennica vol. 13 no. 4 article id 5050
Nyyssönen A., (1979) Assessment of forest resources for forest manage.. Silva Fennica vol. 13 no. 3 article id 5045
Nyyssönen A., (1973) Book review: Forest inventory Silva Fennica vol. 7 no. 4 article id 4892
Nyyssönen A., (1969) Co-operation between research workers at the uni.. Silva Fennica vol. 3 no. 2 article id 4792
Nyyssönen A., Poso S. (1962) Tree stand classifications from aerial photograp.. Silva Fennica vol. no. 112 article id 4705
Nyyssönen A., (1950) Comparative study on structure and development o.. Silva Fennica vol. no. 68 article id 4600
Nyyssönen A., Poso S. et al. (1968) The use of aerial photographs in the estimation .. Acta Forestalia Fennica vol. 82 no. 4 article id 7177
Nyyssönen A., Kilkki P. et al. (1967) On the precision of some methods of forest inven.. Acta Forestalia Fennica vol. 81 no. 4 article id 7169
Nyyssönen A., Kilkki P. (1966) Estimation of strata areas in forest survey Acta Forestalia Fennica vol. 81 no. 3 article id 7168
Nyyssönen A., Kilkki P. (1965) Sampling a stand in forest survey Acta Forestalia Fennica vol. 79 no. 4 article id 7162
Nyyssönen A., (1963) Analysis of two alternative methods for national.. Acta Forestalia Fennica vol. 76 no. 6 article id 7146
Nyyssönen A., Vuokila Y. (1963) The effect of stratification on the number of sa.. Acta Forestalia Fennica vol. 75 no. 2 article id 7136
Kuusela K., Nyyssönen A. (1962) The cutting budget for a desirable growing stock Acta Forestalia Fennica vol. 74 no. 6 article id 7133
Nyyssönen A., (1959) Finnish research in the fields of forest mensura.. Acta Forestalia Fennica vol. 70 no. 6 article id 7496
Nyyssönen A., (1959) Finnish research in the fields of forest mensura.. Acta Forestalia Fennica vol. 70 no. 5 article id 7495
Nyyssönen A., (1954) Structure and development of Scots pine stands t.. Acta Forestalia Fennica vol. 60 no. 4 article id 7411
Holopainen V., Nyyssönen A. et al. (1984) The 75th Anniversary volume of the Society of Fo.. Acta Forestalia Fennica vol. 0 no. 190 article id 7645
Nyyssönen A., Ojansuu R. (1982) Assessment of timber assortments, value and valu.. Acta Forestalia Fennica vol. 0 no. 179 article id 7626
Nyyssönen A., Mielikäinen K. (1978) Estimation of stand increment Acta Forestalia Fennica vol. 0 no. 163 article id 7597
Nyyssönen A., Roiko-Jokela P. et al. (1971) Studies on improvement of the efficiency of syst.. Acta Forestalia Fennica vol. 0 no. 116 article id 7550