An empirical test of the Balassa-Samuelson hypothesis: Evidence from eight middle-income countries in Africa

The paper tests the validity of the Balassa-Samuelson hypothesis (BSH) using the within-effects and the dynamic panel generalised methods of moment (GMM) techniques for a panel of eight middle-income African countries over the period 1960–2009. We selected these countries because they exhibited a mixture of relative productivity growth and real exchange rate misalignment that fits the characterization of the BSH well. The results strongly support the BSH for this group of countries. The results are valid even after we controlled for potentially omitted variables and endogeneity. The implication is that as these countries become more productive, their currencies appreciate in real terms.     

Agricultural productivity growth in Latin America and the Caribbean: an analysis of climatic effects,catch‐up and convergence*

This paper investigates whether climatic adjusted total factor productivity (CATFP) in Latin America and the Caribbean (LAC) is converging, converging to different steady states or exhibit absolute convergence, that is the process does not require (government) interventions to reach its equilibrium path. We use data from the University of East Anglia’s Climatic Research Unit and from the Food and Agriculture Organization for 28 LAC countries over a 54‐year period (1961–2014) to estimate random parameters stochastic production frontier models to calculate CATFP and then use cross‐sectional regressions and an error correction model to analyse CATFP convergence across countries in the region. The results show that technological progress is the main driver of CATFP growth in the region and there is no absolute convergence, that is CATFP gaps across countries will not decrease over time and least performing countries will not grow faster than better performing ones without targeted policies. However, CATFP across LAC exhibits conditional convergence towards different steady states. Technological progress plays a critical role in raising the steady state level of CATFP with an overall average of 2.22 per cent per annum.     

基于AE的土地生产潜力评价信息系统的设计与实现

土地生产潜力评价是土地资源合理高效利用的基础,其使用的数学评价模型计算复杂、过程繁琐、评价结果抽象,因此具有综合性、实践性、基础性的特点。利用GIS所具有的强大空间数据存储、处理、分析和可视化的能力,可以弥补现有土地潜力评价模型的不足,更好地为土地资源管理提供支撑和保障。文章基于Arc GIS Engine(AE)二次开发组件、地理数据库技术、土地生产潜力评价模型,利用VS2010开发了土地生产潜力评价信息系统。系统集成了数据加载、数据管理、数据查询、数据编辑、空间分析和潜力评价以及专题图制作等功能,具备性能运行稳定、评价效率高,数据可视化等特点。以河南省为例进行了土地生产潜力分析评价,得到可靠、直观的评价结果。研究验证了土地生产潜力评价GIS系统开发的可行性,为土地管理、农业生产规划等提供管理和分析工具。     

Employment and absenteeism in working-age persons with multiple sclerosis

Aims: To better understand the impact of the clinical course of multiple sclerosis (MS) and disability on employment, absenteeism, and related factors.

Materials and methods: This study included respondents to the North American Research Committee on Multiple Sclerosis Registry spring 2015 update survey who were US or Canadian residents, aged 18–65 years and reported having relapsing-remitting MS (RRMS), secondary progressive MS (SPMS), or primary progressive MS (PPMS). The RRMS and SPMS participants were combined to form the relapsing-onset MS (RMS) group and compared with the PPMS group regarding employment status, absenteeism, and disability. Multivariable logistic regression was used to examine the relationship between employment-related outcomes and factors that may affect these relationships.

Results: Of the 8004 survey respondents, 5887 (73.6%) were 18–65 years of age. The PPMS group (n?=?344) had a higher proportion of males and older mean age at the time of the survey and at time of diagnosis than the RMS group (n?=?4829). Female sex, age, age at diagnosis, cognitive and hand function impairment, fatigue, higher disability levels, ≥3 comorbidities, and a diagnosis of PPMS were associated with not working. After adjustment for disability, the employed PPMS sub-group reported similar levels of absenteeism to the employed RMS sub-group.

Limitations: Limitations of the study include self-report of information and the possibility that participants may not fully represent the working-age MS population.

Conclusions: In MS, employment status and absenteeism are negatively affected by disability, cognitive impairment, and fatigue. These findings underscore the need for therapies that prevent disability progression and other symptoms that negatively affect productivity in persons with MS to enable them to persist in the workforce.     

The public R&D and productivity growth in Australia's broadacre agriculture: is there a link?

This paper investigates the dynamic relationships between research and development (R&D) expenditure and productivity growth in Australian broadacre agriculture using aggregate time series data for the period 1953 to 2009. The results show a cointegrating relationship between R&D and productivity growth and a unidirectional causality from R&D to TFP (total factor productivity) growth in Australian broadacre agriculture. Using the dynamic properties of the model, data from beyond the sample period are analysed by employing the variance decomposition and the impulse response function. The findings reveal that R&D can be readily linked to the variation in productivity growth beyond the sample period. Furthermore, the forecasting results indicate that a significant out‐of‐sample relationship exists between public R&D and productivity in broadacre agriculture.     

The relationship between business diversification and productivity: considering the impact of process innovation at different corporate life cycles

This paper investigates the link between a firm's process innovation (PI) and its segment productivity at different life cycles. The results show that business diversification is negatively associated with a firm's productivity, and further reveal that a firm's PI moderates the above relationship. In addition, the corporate life cycle literature builds blocks for this study to explain that the involvement of administrative costs varies across life cycles when diversified firms get mature and bigger. Our empirical evidence indicates that the potential costs of a complex organisational structure contingent on business diversification at a firm's mature life cycle could be alleviated by the conduct of process innovation. As process innovation at different life cycles may alter managerial incentive that leads to different firm performance, the managerial implication is that diversified firms should appropriately engage in process innovation to prevent unfavourable liability from the development of their businesses.     

西部现代服务业主导产业选择——基于技术进步的视角

一个地区在其现代服务业的发展过程中,如何因地制宜地选择和培育现代服务业主导产业是其在经济发展过程中需要认真思考的问题。文章从技术进步的视角出发,在对我国西部地区服务业各细分行业进行资本存量估算的基础上,分析和测度服务业各细分行业的全要素生产率(TFP)和技术进步率,并建立现代服务业主导产业的选择指标体系,采用因子分析法对各指标体系进行实证分析,最终确定批发零售贸易和餐饮业、房地产业、信息传输及计算机服务和软件业、租赁和商务服务业、交通运输及仓储和邮政业、卫生及体育和社会福利业为我国西部地区现代服务业主导产业。