民间传奇与完整长度——90年代长篇小说所追求的两大奇书叙事特征

民间意味着自由自在,是一种充满了日常情趣的生活场景;而传奇则意味着曲折诡异,有一种超越常规的神奇品性。五大奇书之所以经久不衰,就是因为奇书叙事中同时包含了“民间”和“传奇”这两大元素,既拥有民间的立场,又有传奇的故事。在20世纪90年代的长篇小说中,我们也能强烈地感受到这种民间的气息和叙事上的传奇性。奇书叙事的另一特征就是追求完整长度,受“进化论”的影响,五六十年代的革命历史小说呈现出一种断裂性叙事,而90年代长篇小说所追求的是整体性叙事。

Gaussian mixture model clustering with completed likelihood minimum message length criterion

An improved Gaussian mixture model （GMM）- based clustering method is proposed for the difficult case where the true distribution of data is against the assumed GMM. First, an improved model selection criterion, the completed likelihood minimum message length criterion, is derived. It can measure both the goodness-of-fit of the candidate GMM to the data and the goodness-of-partition of the data. Secondly, by utilizing the proposed criterion as the clustering objective function, an improved expectation- maximization （EM） algorithm is developed, which can avoid poor local optimal solutions compared to the standard EM algorithm for estimating the model parameters. The experimental results demonstrate that the proposed method can rectify the over-fitting tendency of representative GMM-based clustering approaches and can robustly provide more accurate clustering results.