The role of capital-labour substitution in economic growth

Purpose – Although the importance of the elasticity of substitution between capital and labour (s) has been recognized in many areas in economics, this parameter has not received enough attention in economic growth. The purpose of this paper is to review the recent development in the importance of s in economic growth.

Design/methodology/approach – This paper specifically reviews the possibility of perpetual growth and slowdown, and the asymptotic behaviour of the balanced growth path for different values of s. It also reviews the determinants of the aggregate s.

Findings – Based on the empirical evidence that the value of s significantly departs from the Cobb-Douglas value of unity, the paper recommends employing the constant elasticity of substitution (CES) production function in both theoretical and empirical growth research.

Originality/value – This paper offers a new perspective on the elasticity of substitution between capital and labour due to its evaluation of various factors, methods and approaches.

Space-for-time substitution to assess likely response of aquatic ecosystems to future climate-related change

Predicting and managing ecological response to a changing climate is often limited by an incomplete understanding of response thresholds and biogeographic differences. For example, step changes in rainfall and runoff, and threshold dynamics and hysteresis in ecological response make projection of future conditions difficult. To combat these constraints we propose that biophysical data across exiting climatic gradients can be used in a space-for-time substitution to predict climate-related ecological response elsewhere. This method builds on previous attempts at space-for-time substitution by using patterns in physical and physicochemical data to explain biological differences across the spatial gradient, then using those patterns to formulate hypotheses of temporal ecological response and finally testing those hypotheses on temporal data available in a second, similar region of interest. 

Body mass index, sexual difficulties and sexual satisfaction among people in regular heterosexual relationships : a population-based study

Background/Aims:  The aims of this study were to clarify the relationship between body mass index (BMI) and sexual difficulties and to investigate if BMI influenced sexual satisfaction, over and above the effects of sexual difficulties.

Methods:  Cross-sectional analyses of a nationally representative computer-assisted telephone interview. Eight thousand, six hundred and fifty-six respondents were recruited by random digit dialling in 2004–2005. Only those in a sexually active, heterosexual relationship were included in the current analyses.

Results:  After adjustments for demographic factors, both overweight and obese male and female participants were more likely to report worrying during sex about whether their body was unattractive. Among women, associations were also found between higher BMI and lack of interest in sex. No other significant associations between BMI and sexual difficulties were evident. There was an association between BMI and extreme physical pleasure for women but not men over and above the effects of sexual difficulties, with obese women being more likely than normal weight women to report extreme physical pleasure. No associations were found for either men or women between BMI and whether or not they reported extreme emotional or sexual satisfaction with their relationship.

Conclusions:  With the exception of body image difficulties, there is little association between BMI and self-reported sexual difficulties. Furthermore, extreme sexual and emotional satisfaction appeared to be associated with the presence or absence of sexual difficulties and not overly influenced by BMI. Overall, clinicians and patients should be aware that being overweight is not necessarily detrimental to sexual functioning.