公有住房使用权收益价格评估

公有住房使用权价格评估是公房使用权有偿转让的基础性工作,但因我国的公房使用权有别于一般租赁产权,故房地产估价的常观收益法在此并不全然适用。文章在分析我国公房使用权特殊性的基础上,变通了既有的收益法估价公式,提出了确定相关技术参数的思路。作为讨论结果的具体应用,文章最后给出了一宗评估案例。     

论城市土地的依法经营

从法与经济结合的角度,论述了城市土地经营的内容,对象,性质,经营模式和投资方式,分析了城市土地的依法经营问题。     

A scalable approach to mapping annual land cover at 250 m using MODIS time series data: A case study in the Dry Chaco ecoregion of South America

Land use and land cover (LULC) maps from remote sensing are vital for monitoring, understanding and predicting the effects of complex human-nature interactions that span local, regional and global scales. We present a method to map annual LULC at a regional spatial scale with source data and processing techniques that permit scaling to broader spatial and temporal scales, while maintaining a consistent classification scheme and accuracy. Using the Dry Chaco ecoregion in Argentina, Bolivia and Paraguay as a test site, we derived a suite of predictor variables from 2001 to 2007 from the MODIS 250 m vegetation index product (MOD13Q1). These variables included: annual statistics of red, near infrared, and enhanced vegetation index (EVI), phenological metrics derived from EVI time series data, and slope and elevation. For reference data, we visually interpreted percent cover of eight classes at locations with high-resolution QuickBird imagery in Google Earth. An adjustable majority cover threshold was used to assign samples to a dominant class. When compared to field data, we found this imagery to have georeferencing error < 5% the length of a MODIS pixel, while most class interpretation error was related to confusion between agriculture and herbaceous vegetation. We used the Random Forests classifier to identify the best sets of predictor variables and percent cover thresholds for discriminating our LULC classes. The best variable set included all predictor variables and a cover threshold of 80%. This optimal Random Forests was used to map LULC for each year between 2001 and 2007, followed by a per-pixel, 3-year temporal filter to remove disallowed LULC transitions. Our sequence of maps had an overall accuracy of 79.3%, producer accuracy from 51.4% (plantation) to 95.8% (woody vegetation), and user accuracy from 58.9% (herbaceous vegetation) to 100.0% (water). We attributed map class confusion to limited spectral information, sub-pixel spectral mixing, georeferencing error and human error in interpreting reference samples. We used our maps to assess woody vegetation change in the Dry Chaco from 2002 to 2006, which was characterized by rapid deforestation related to soybean and planted pasture expansion. This method can be easily applied to other regions or continents to produce spatially and temporally consistent information on annual LULC.     

信息技术的需求方法研究

现在处于一个信息技术高速发展时期,这些年来单位信息系统逐步建立、升级,给各个生产业务部门带来了助力。随着世界范围内信息技术的广泛应用,生产业务部门人员的IT技能越来越高,对软件系统的使用要求也越来越多。这是一件可喜的事情,说明信息技术创新,助力业务创新,已经有了良好的群众基础。在IT业界,众多的成功或不成功案例都实践证明,一个应用系统最后是否建设成功,80%的因素在于需求分析是否做得好。浅显发地说,也就是:业务部门人员是否把需要实现的软件系统功能都说明白了,没有较大的遗漏;开发人员都理解清楚了,没有较大的偏差。该文就如何做好需求分析工作,进行简要论述。     

Organizational Norm Congruency and Interpersonal Familiarity in E‐Mail: Examining Messages From Two Different Status Perspectives

Relying on SIDE theory, this 2 × 2 experimental design tested the effects of adherence to organizational norms and interpersonal familiarity in e‐mail messages from both superior and subordinate perspectives. Results reveal that using norm‐congruent e‐mail messages account for over 50% of the variance in both superior and subordinate attitudes toward the message and between 30% and 56% of the variance in perceptions of source credibility. Data from the superiors indicate that norm congruent e‐mail messages account for 14.4% of the variance in message compliance. Results from subordinates reveal an interaction effect that is consistent with SIDE‐based predictions. Subordinates believe superiors are most likely to comply with e‐mail requests from unfamiliar subordinates that are crafted in a manner congruent with organizational norms.     

Psychometric properties of the Problematic Internet Use Questionnaire

Several instruments have been designed to measure problems associated with excessive, compulsive, or addictive use of the Internet. One such instrument, the 18-item Problematic Internet Use Questionnaire, was recently published with data supporting a three subscale model (Demetrovics et al., 2008). These researches utilized an online format with a sample taken from the general population of Hungary. We utilized an American college student sample and a paper and pencil format to perform a confirmatory factor analysis of the PIUQ. In addition, we examined the reliability and construct validity of the PIUQ by examining the scales’ relationship with several indices of psychological and physical health. CFA results indicate a barely adequate and not completely problem free three factor model for the PIUQ (χ² = 477.40; root mean square error = .097; comparative fit index = .831; Tucker Lewis coefficient = .804). Cronbach’s α for the total scale was .91 while the Cronbach’s α for each subscale were .81, .77, and .79. Construct validity for the model is demonstrated with significant correlations between the subscales and several indices of psychological and physical health. Suggestions for further research are provided.     

Is compulsive internet use related to sensitivity to reward and punishment,and impulsivity?

Aim of the present study was to examine whether the personality correlates sensitivity to reward and to punishment, and impulsivity predict compulsive internet use (CIU). Furthermore, the predictive value of these personality correlates was compared to the predictive value of factors relating to psychosocial wellbeing. The results showed that particularly rash spontaneous impulsivity predicts CIU and that this personality factor is more important than psychosocial wellbeing factors. Sensitivity to reward, which is supposed to play a role in craving processes associated with substance abuse and eating disorders, could not be related to CIU. The data suggest that internet users who are characterized by an impulsive personality feature, are less able to control their use of the internet, which makes them more vulnerable to develop CIU.     

Internet use, videogame playing and cell phone use as predictors of children’s body mass index (BMI), body weight, academic performance, and social and overall self-esteem

In this research we examined the prediction of children’s body mass index (BMI), body weight, academic performance, social self-esteem and overall self-esteem from their IT (information technology) use, specifically, their Internet use, cell phone use and videogame playing, after controlling for the effects of gender, race, age and household income on these measures. Participants were 482 children whose average age was 12 years old. One-third was African American and two-thirds were Caucasian American. Results indicated that IT use did not predict BMI or body weight, contrary to one previous survey and the widespread belief that screen time is responsible for the obesity epidemic among our nation’s children. Instead, BMI and body weight were higher for African Americans, older children and children from lower income households. The sole and strong positive predictor of visual-spatial skills was videogame playing, which also predicted lower grade point averages (GPAs). Gender and Internet use predicted standardized test scores in reading skills. Females and children who used the Internet more had better reading skills than did males and children who used the Internet less, respectively. Implications of these findings for future research on the benefits and liabilities of IT use are discussed.     

Should I e-collaborate with this group? A multilevel model of usage intentions

The use of online collaboration tools for virtual teamwork has been studied extensively, but mainly at the individual-level. We decided to examine the effect of macro-level factors (i.e., team attributes) and applied hierarchical linear modeling analysis to a sample of data collected from 96 individuals nested in 34 virtual teams. Our results suggested that the development of behavioral e-collaboration intentions by individual virtual team members was affected by their perceptions about the system, as described by individual-level IT use theories, and macro-level factors pertaining to the team. The collaboration technology was perceived to be less useful when employed to communicate with social loafers; and collective social loafing negatively influenced the teams’ potency assessments. After controlling for individual-level perceptions of system usefulness, team potency augmented team members’ intentions to use the online collaboration technology with similar teams. It also improved team performance.     

A longitudinal experimental study on the interaction effects of persuasion quality, user training, and first-hand use on user perceptions of new information technology

While prior research has investigated the main effects of external factors on user perceptions of a new IT, little work has been into the interaction effect of external factors on user perceptions. In a longitudinal experimental study, we examined the effect of the quality of persuasive argument, user training, and first-hand use on user perceptions of the new technology over time. We found that the effect of argument quality on users’ perceived ease of use was greater when users had no training. However, we did not find the same effect occurred due to perceived usefulness. We also found that first-hand use changed users’ perceived usefulness more over time when users received high quality arguments or when they had no training. While we found that first-hand use changed users’ perceived ease of use more when users received high quality arguments, first-hand use did not change users’ perceived ease of use differently whether they had or had not received prior training.