变点分析法(change point analysis,CPA)近些年才引入心理与教育测量学,相较于传统方法,CPA不仅可以侦查异常作答被试,还能自动精确地定位变点位置,高效清洗作答数据。其原理在于:判断作答序列中是否存在可将该序列划分为具有不同统计...变点分析法(change point analysis,CPA)近些年才引入心理与教育测量学,相较于传统方法,CPA不仅可以侦查异常作答被试,还能自动精确地定位变点位置,高效清洗作答数据。其原理在于:判断作答序列中是否存在可将该序列划分为具有不同统计学属性两部分的点(即变点),并且需使用被试拟合统计量(person-fit statistic,PFS)来量化两个子序列之间的差异。未来可将单变点分析拓展至多变点,结合反应时等信息,构建非参数化指标以及将现有指标拓展至多级计分或多维测验,以提高CPA的适用广度及效力。展开更多
Five multiparameter empirical criteria were exclusively evaluated by comparing them with the strength data covering various stress conditions to find out which failure criterion best fits the test data and describes t...Five multiparameter empirical criteria were exclusively evaluated by comparing them with the strength data covering various stress conditions to find out which failure criterion best fits the test data and describes the mechanical behavior of the salt rock sequence (halite,bedded composite specimens and anhydrite interlayers).Full-scale comparison of all criteria for the three rock types was conducted based on five standard statistics calculated from least squares curve-fitting,which measures both the goodness of fitting and the quality of future prediction.The results indicate that all five nonlinear criteria with a basic power form are efficient in predicting the strength trend in the low tension area as well as in the high compression area of the soft rocks.The parameters obtained for the bedded rock salt are somewhat in the ones for the "pure" rocks and are even closer to those obtained for the halite.The generalized Hoek-Brown criterion is proven to perform best to two rock strength data followed by one for the Bieniawski empirical criterion,thus is the best candidate for the analysis of the salt rock.The Sheorey empirical criterion consistently achieves an intermediate performance for all the three rocks.It seems that the superiority of the poly-axial criteria (the Mogi 1967 criterion and the N-type criterion) over the former three triaxial criteria no longer exists when applied to the conventional triaxial strength data.Besides,the method of tension cut-off was proposed to solve the ambiguity problem of the two poly-axial criteria in the tension field in the plane of the major (σ1) andminor principal stress (σ3).展开更多
文摘变点分析法(change point analysis,CPA)近些年才引入心理与教育测量学,相较于传统方法,CPA不仅可以侦查异常作答被试,还能自动精确地定位变点位置,高效清洗作答数据。其原理在于:判断作答序列中是否存在可将该序列划分为具有不同统计学属性两部分的点(即变点),并且需使用被试拟合统计量(person-fit statistic,PFS)来量化两个子序列之间的差异。未来可将单变点分析拓展至多变点,结合反应时等信息,构建非参数化指标以及将现有指标拓展至多级计分或多维测验,以提高CPA的适用广度及效力。
基金Project(2009CB724608) supported by the National Basic Research Program of China
文摘Five multiparameter empirical criteria were exclusively evaluated by comparing them with the strength data covering various stress conditions to find out which failure criterion best fits the test data and describes the mechanical behavior of the salt rock sequence (halite,bedded composite specimens and anhydrite interlayers).Full-scale comparison of all criteria for the three rock types was conducted based on five standard statistics calculated from least squares curve-fitting,which measures both the goodness of fitting and the quality of future prediction.The results indicate that all five nonlinear criteria with a basic power form are efficient in predicting the strength trend in the low tension area as well as in the high compression area of the soft rocks.The parameters obtained for the bedded rock salt are somewhat in the ones for the "pure" rocks and are even closer to those obtained for the halite.The generalized Hoek-Brown criterion is proven to perform best to two rock strength data followed by one for the Bieniawski empirical criterion,thus is the best candidate for the analysis of the salt rock.The Sheorey empirical criterion consistently achieves an intermediate performance for all the three rocks.It seems that the superiority of the poly-axial criteria (the Mogi 1967 criterion and the N-type criterion) over the former three triaxial criteria no longer exists when applied to the conventional triaxial strength data.Besides,the method of tension cut-off was proposed to solve the ambiguity problem of the two poly-axial criteria in the tension field in the plane of the major (σ1) andminor principal stress (σ3).
