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机构地区:[1]山东棉花研究中心,山东济南250100 [2]山东省果树研究所,山东泰安271000
出 处:《山东农业科学》2012年第2期112-116,共5页Shandong Agricultural Sciences
摘 要:利用布拉德福(Bradford)定律发展而来的布鲁克斯(Brookes)图形法计算核桃专业核心期刊时,由于核桃专业属于农业类的狭窄专业,可采用的期刊实体样本空间狭小,因而会产生较大的系统误差,而在实际统计中,期刊实体增量十分有限,即短期内通常不会有大量的新增实体样本出现。本研究通过β曲线辅助分析法得到了可靠的核桃专业核心期刊布鲁克斯图形分界点,并利用这一分界点逆推得到布鲁克斯图形法误差修正系数。Because walnut specialty is a narrow specialty in agriculture,the adoptable journal samples were fewer,which resulted in bigger systematic error when the graphic method of Brookes developed from Bradford law was used to calculate walnut specialty core journals.In actual statistics,the increase quantity of journal entity was limited,namely the appearance of big increase of new entity samples was generally impossible in short period.A dependable boundary point of Brookes figure on walnut specialty core journal was obtained from the method of β-curve supplemental analysis,and then an error correction coefficient of the graphic method of Brookes was obtained by backward inference from this point.
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