The Market for Picasso Prints: A Hybrid Model Approach

Two basic approaches have been used by the literature focusing on the return to holding artistic works: the hedonic price model and the repeat-sales model. This paper provides a procedure for jointly estimating the two models in a way that take advantages of the unique information contained in each. A semiannual price index for Picasso prints is estimated by using a model derived from the basic framework of the hybrid models. The empirical results suggest that the hybrid model provides the most precisely estimated price index by reducing the level of price volatility.JEL Classification: C5, Z1p     

The discrete charm of the bourgeoisie: quantum and continuous perspectives on innovation and growth

This paper discusses the relative merits of discrete versus continuous perspectives on innovation, technical change, and economic growth. It discusses the innovation time series literature in some detail to extract the continuous and clustering properties of the historical record on innovation. It then proposes a mosaic/avalanche model based on percolation theory and self-organized criticality to address this question.     

基于数理模型的新建高校学生资助工作创新

本文针对新建高校在家庭经济困难学生认定、资助过程中存在的问题,创新采用模糊综合评价理论、PDCA循环理论等模型,在家庭经济困难学生资助工作中开展动态化管理,从而使资助体系更加科学有效。     

论大学生成长成才的“四个平台建设”——从大学班集体角度思考

大学生成长成才是高校人才培养的目的。从大学班集体角度进行阐述,认为通过思想教育平台建设、自我发展平台建设、专业展示平台建设、爱心行动工程建设等＂四个建设＂,能更好地促使学生成长成才。     

强制对流和高各向异性对枝晶生长的影响

基于修正的Wheeler相场模型,建立耦合溶质场、温度场和流场的相场模型,研究Ni-Cu合金凝固过程中高各向异性作用下的枝晶生长行为。结果表明:各向异性强度在0.06-0.2之间取值时,随着各向异性强度增加,光滑主枝尖端出现棱角,枝晶尖端生长速度先增加后减小。在高各向异性条件下,有无对流时晶粒分别以不对称枝晶和等轴枝晶方式生长。在流速为6.43 m.s-1的强制对流作用下,逆流侧枝晶受过冷熔体冲刷,逆流枝晶生长迅速,与纯扩散时相比稳态生长速度增加了12.61%;热量和溶质在顺流侧聚集,顺流枝晶生长缓慢,与纯扩散时相比稳态生长速度减小了14.62%。     

植物生长调节剂对小麦产量及产量构成的影响

本研究了叶面喷施几种植物生长调节剂(GA3、NBT、6—BA、TIBA、PP333)对小麦分蘖、生育后期生理指标、产量构成因素和产量的影响。     

Development and Application of a Two-Tier Diagnostic Test for High School Students’ Understanding of Flowering Plant Growth and Development

This study involved the development and application of a two-tier diagnostic test measuring students understanding of flowering plant growth and development. The instrument development procedure had three general steps: defining the content boundaries of the test, collecting information on students misconceptions, and instrument development. Misconception data were collected from interviews and multiple-choice questions with open response answers. The data were used to develop 13 two-tier multiple-choice items. The conceptual knowledge examined was flowering plant life cycles, reproduction, precondition of germination, plant nutrition, and mechanism for growth and development. The diagnostic instrument was administered to 477 high school students. The correlation coefficient of test-retest was 0.75. Difficulty indices ranged from 0.24 to 0.82, and discrimination indices ranged from 0.32 to 0.65. Results of the Flowering Plant Growth and Development Diagnostic Test suggested that students did not acquire a satisfactory understanding of plant growth and development concepts. Nineteen misconceptions were identified through analysis of the items that could inform biology instruction and resource.