Journal of Korean Society of Forest Science (한국산림과학회지)
- Volume 65 Issue 1
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- Pages.68-73
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- 1984
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- 2586-6613(pISSN)
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- 2586-6621(eISSN)
Comparison of Simple Random Sampling and Two-stage P.P.S. Sampling Methods for Timber Volume Estimation
임목재적(林木材積) 산정(算定)을 위(爲)한 Simple Random Sampling과 Two-stage P.P.S. Sampling 방법(方法)의 비교(比較)
- Kim, Je Su (Forest Research Institute) ;
- Horning, Ned
- 김재수 (임업시험장) ;
- Received : 1984.07.09
- Published : 1984.09.30
Abstract
The purpose of this paper was to figure out the efficiencies of two sampling techniques, a simple random sampling and a two-stage P.P.S. (probability proportional to size) sampling, in estimating the volume of the mature coniferous stands near Salzburg, Austria. With black-and-white infrared photographs at a scale 1:10,000, the following four classes were considered; non-forest, young stands less than 40 years, mature beech and mature coniferous stands. After the classification, a field survey was carried out using a relascope with a BAF (basal area factor) 4. For the simple random sampling, 99 points were sampled, while for the P.P.S. sampling, 75 points were sampled in the mature coniferous stands. The following results were obtained. 1) The mean standing coniferous volume estimate was
Simple random sampling과 P.P.S. sampling의 효율을 비교하기 위하여 오스트리아 Salzburg 부근의 침엽수 장령림 임분에서 임목조사를 실시하였다. 축적 1:10,000의 흑백 적외선 사진을 판독하여, 조사 임지를 제지, 유령림, 너도 밤나무 장령림, 침엽수 장령림으로 구분하고, 침엽수 장령림 내에서 random sampling에 의한 99개의 표본점과 P.P.S. sampling에 의한 75개의 표본점을 흉고 단면적 제수 4인 Relascope에 의하여 야외 조사한 자료를 비교한 결과는 다음과 같다. 1) random sampling에 의한 임분 재적의 추정치는
Keywords
- simple random sampling;
- two-stage P.P.S. sampling;
- forest inventory;
- black-and-white infrared photograph