混合地理加权回归模型的拟合及相关性检验

利用两步估计方法对混合地理加权回归模型进行拟合,运用Moran's检验方法探索误差项的空间相关性。     

混合双寡头模型下的R&D竞争:不确定性和模仿视角

通过引入模仿参数δ来衡量R&D容易被模仿的程度,对Joanna Poya-go-Theotoky(1998)的研究进行了拓展,验证了其基本结论的稳健性。此外,通过引入二次R&D成本函数,研究发现,混合双寡头与私人双寡头情况下的社会福利的比较是不确定的,除了依赖创新规模P以外,还取决于模仿参数d,即——(1)对于任意的d,创新规模越大,私人双寡头越倾向于占优混合双寡头,混合双寡头仅在创新规模较小的时候可能优于私人双寡头;(2)对于创新规模比较小的R&D,只有同时具备较容易的模仿程度,混合双寡头才会优于私人双寡头;(3)在不完全模仿(d≠1)的情况下,在R&D越来越容易被模仿的过程中,利率越高(低),私人双寡头优于混合双寡头的最低P值先上升(下降)后下降(上升)。     

Modeling Disinterest and Dislike: A Bounded Bayesian Mixed Logit Model of the UK Market for GM Food

Mixed logit models represent a powerful discrete choice analytical model but require assumptions about the functional form of the parameter distributions. The use of unbounded distributions, such as the normal distribution, may be regarded as unsuitable where theory indicates that all are negatively affected by increases in an attribute, such as price. Bounded distributions such as the triangular and log-normal are unable to model the case where a section of the population is indifferent towards an attribute, while the remainder are negatively disposed toward it. Train and Sonnier’s bounded mixed logit model accommodates these features and is employed in this paper. A censored normal and Johnson’s S_b distribution are used to model preferences in the UK for food attributes, including price and GM technology. Bi-modal distributions are identified regarding GM food: some are unlikely to ever consume it, some are close to indifference and willing to consume at relatively small discounts while the remainder are fairly unresponsive to further price reductions.     

东北地区粮食型农户家庭农场经营风险认知的影响因素分析

［目的］东北地区作为维护国家粮食安全的“压舱石”,准确而系统地掌握东北地区粮食型农户家庭农场经营风险认知水平,为政府部门精准实施粮食型农户家庭农场配套扶持政策提供参考。［方法］文章利用黑龙江、吉林、辽宁3省301个粮食型农户家庭农场调研数据,运用交叉列表和多元有序logit模型分析家庭农场经营风险认知水平及其影响因素。［结果］（1）6312%的粮食型家庭农场有一定风险认知能力,土地经营面积在333~1333hm2（50~200亩）与1333~3333hm2（200~500亩）的家庭农场风险认知处于中等水平, 3333hm2（500亩）以上家庭农场经营风险认知低; （2）玉米种植型家庭农场风险认知水平高于水稻种植型家庭农场; （3）年龄、是否村干部、劳动力数量、土地经营规模、是否有自然灾害、农产品市场价格波动、是否“三品一标”认证、金融支持、农推人员技术指导和新型经营主体间合作稳定对东北地区粮食型农户家庭农场经营风险认知有影响。［结论］应培养家庭农场主个人特质,鼓励支农惠农政策向规模适度的家庭农场倾斜,从流程入手提高家庭农场风险防范能力。     

A Dynamic Analysis of Fixed- and Adjustable-Rate Mortgage Terminations

This paper provides a side-by-side comparison of loan-level statistical models for fixed- and adjustable-rate mortgages. Multinomial logit models for quarterly conditional probabilities of default and prepayment are estimated. We find that the estimated impacts of embedded option values for prepayment and default are generally quite similar across both FRM and ARM loans, providing additional empirical support for the basic predictions of the options theory. We also find that differences in estimates of conditional probabilities of prepayment and default associated with mortgage age, origination period, original LTV, and relative loan size, indicate the continued significance of these other economic and demographic factors for empirical models of mortgage terminations.     

Biotechnology as a Technological Paradigm in the Global Knowledge Structure

The aim of this study is to analyse whether the receipt of public R&D funding determines firm's R&D strategy selection. This issue is crucial, as previous studies have shown that each R&D strategy is associated to a higher, or lower, innovation performance. We consider three R&D strategies – make, buy, make–buy – and three different sources of public funding – regional, state and other (such as EU). The model estimation is performed through a multinomial logit model with random effects with a sample of 457 large firms for the period 1992–2005, taken from the Spanish Survey of Business Strategies. The main finding is that the source of the funding influences whether firms select the make, buy or make–buy strategy. Additionally, because of the panel structure of the sample, we observe that the effect of public funding on the R&D strategy selection lasts longer for state and regional funds than for other funds.     

Modeling Overnight Recreation Trip Choice: Application of a Repeated Nested Multinomial Logit Model

In this paper we apply the repeated nested multinomial logit model, a version of a random utility model (RUM), to estimate the choice of an overnight versus single day recreation trip, along with the other usual choice of which of the sites to visit, and less typically, the choice of whether to participate (in our application – to fish) at all. We also find statistically significant income effects in the empirical results. The application is to Atlantic Salmon fishing and the data set is for Maine resident angler's fishing trips to rivers in Maine and Canada.