摘要
本文采用功率谱分析、周期图分析、方差分析以及计算转移概率等多种统计分析方法，对４０年来延边地区粮食产量的变化特点进行了分析。结果表明：４０年来，延边地区粮食产量的增年多于减年，增向转移概率也大于减向转移概率，并且粮食的增减产年具有６年及其倍数的波动周期。
This paper adopted power spectrum analysis, periodogram analysis,and variance analysisand calculated transfer probability to analyze the changeable characteristics of grain yield within forty years inYanbian area. Results showed that the increased years of grain yield were more than the decreased years ofthat within forty years in Yanbian area, transfer probability toward adding was bigger than that toward reducing and there was the wave period of six years or its times to the increased or decreased years of grain yield.
