城市农民工与转型期中国社会的三元结构

二元社会结构理论不能完全解释中国城市化过程中所出现的大量城市农民工现象 ,因受户籍管理制度的限制 ,他们不可能在较短时间内转化为城市居民。城市农民工是转型期中国社会的特殊群体 ,他们既不同于农村居民 ,也不同于城市居民。城市农民工群体人数众多 ,存在时间较长 ,对社会影响较大 ,足以构成转型期中国社会的第三元。新三元的出现 ,将给城乡二元社会发展带来一系列的问题与挑战 ,不可不研究     

试论不动产双重买卖与撤销权之行使

不动产双重买卖是否有效 ,学术界历来有争议。不动产双重买卖并非法律所禁止行为 ,但债权人 (先买受人 )在一定条件下可行使撤销权。撤销权行使之后果是使债务人(出卖方 )的双重买卖行为自始无效 ,债务人已失之财产又恢复原状 ,复归于其 ,从而债权人可达到追回不动产之目的。     

认识中介的演化与反映内容的二重性

信号与符号构成主客体之间的认识中介关系 ,信号是对象物理性质的直接反映 ,而符号则是人文化的信息。符号能区别映象与对象 ,使精神活动相对独立于物质运动。认识中介携带着主客体双方的信息 ,在符号化以后 ,必然有形式的不同 ,这是科学语体与人文语体之差异的来源。     

双重增长极与长江流域有序发展研究

增长极理论自20世纪50年代首次提出以来,广泛运用于世界各国的经济发展和区域规划,特别是对推动发展中国家工业化进程起到了积极作用。长江流域总体上仍处于传统农业社会向现代工业社会转型阶段,少数发达地区知识经济迅速崛起,呈现出农业、工业、知识三大经济形态并存局面。为了实现全流域社会经济有序发展,必须抓住三级经济形态之间两大转型的历史性机遏,同时培育工业化和信息化双重增长极,使长江流域“三级两跳”,即推进由农村、初步工业化地区向现代化大工业转型和发达工业化地区向知识经济转型,使流域发展走向有序化、多元化和国际化。     

二元经济中的农村劳动力转移

中国经济是典型的二元经济,农村中有大量剩余劳动力。将这些劳动力从农村转移到城市是一项艰巨的任务。根据刘易斯模型,投资与工资差距会实现劳动力的转移。近几年,投资的相对不足与较低的农民收入降低了劳动力转移的数量。根据造成这种状况的原因分析,应当实行提高农民收入、减轻农民负担、增加生产性投资、保障农民工利益等相关措施加速劳动力的转移。     

How to avoid concerns with the interpretation of two primary endpoints if significant superiority in one is sufficient for formal proof of efficacy

Formal proof of efficacy of a drug requires that in a prospective experiment, superiority over placebo, or either superiority or at least non-inferiority to an established standard, is demonstrated. Traditionally one primary endpoint is specified, but various diseases exist where treatment success needs to be based on the assessment of two primary endpoints. With co-primary endpoints, both need to be “significant” as a prerequisite to claim study success. Here, no adjustment of the study-wise type-1-error is needed, but sample size is often increased to maintain the pre-defined power. Studies that use an at-least-one concept have been proposed where study success is claimed if superiority for at least one of the endpoints is demonstrated. This is sometimes also called the dual primary endpoint concept, and an appropriate adjustment of the study-wise type-1-error is required. This concept is not covered in the European Guideline on multiplicity because study success can be claimed if one endpoint shows significant superiority, despite a possible deterioration in the other. In line with Röhmel's strategy, we discuss an alternative approach including non-inferiority hypotheses testing that avoids obvious contradictions to proper decision-making. This approach leads back to the co-primary endpoint assessment, and has the advantage that minimum requirements for endpoints can be modeled flexibly for several practical needs. Our simulations show that, if planning assumptions are correct, the proposed additional requirements improve interpretation with only a limited impact on power, that is, on sample size.     

马克思的资本有机构成理论与当代中国的经济发展

马克思在《资本论》中介绍,资本家为了获得更多的剩余价值和在竞争中取胜,必然不断改进技术,采用先进机器设备,提高劳动生产率,其结果是在全部资本中,不变资本所占比重相对增大,而可变资本所占比重相对缩小,从而导致资本有机构成提高。资本有机构成的提高,是资本积累、资本扩张发展的一个必然趋势。可在当今,随着产业结构调整和科学技术的发展,资本有机构成呈现下降的趋势,在发达国家尤其明显,资本有机构成对我国经济也有影响。     

陪都小说的史诗双重建构

陪都小说通过对抗战时期中国生活的全面书写,以战争史诗与生活史诗的双重小说建构达到了现代史诗的中国高度,促进了中国现代文学的战时发展。     

统筹城乡发展的理论视角与核心理念

统筹城乡发展是我国全面建设小康社会和实现社会主义现代化的重大任务。学术界关于统筹城乡发展的研究主要有三种视角：“马克思主义视角”、“二元经济视角”和“地理空间视角”。新时期我国统筹城乡发展的理念是共生共荣、协调和谐。     

Optimal Reserve Prices in Name‐Your‐Own‐Price Auctions with Bidding and Channel Options

Few papers have explored the optimal reserve prices in the name‐your‐own‐price (NYOP) channel with bidding options in a multiple channel environment. In this paper, we investigate a double‐bid business model in which the consumers can bid twice in the NYOP channel, and compare it with the single‐bid case. We also study the impact of adding a retailer‐own list‐price channel on the optimal reserve prices. This paper focuses on achieving some basic understanding on the potential gain of adding a second bid option to a single‐bid system and on the potential benefits of adding a list‐price channel by the NYOP retailer. We show that a double‐bid scenario can outperform a single‐bid scenario in both single‐channel and dual‐channel situations. The optimal reserve price in the double‐bid scenario is no less than that in the single‐bid case. Furthermore, the addition of a retailer‐own list‐price channel could push up the reserve prices in both single‐bid and double‐bid scenarios.