On-line spectrum auctions in TV white spaces for supporting mobile services—A practical manual

This paper considers an approach for dynamic short-term spectrum leasing in TV white spaces (TVWS) using an on-line auction. The secondary spectrum market discussed here is organized by a central entity called the spectrum broker. The auctioned spectrum appears in blocks of available DVB-T channels with some transmit power constraints set-up to protect the primary users (DVB-T receivers). The bidders are institutional spectrum operators (telecommunication companies or service providers), operating in a given area. These players are characterized by heterogeneous demands concerning the spectrum bandwidth, the operation period with temporarily-exclusive rights for using the spectrum and the transmit power needed for successful transmission. Thus, the auctioned objects are non-identical and present different value for different players. Two auction models are proposed. The first one is the simultaneous auction in time domain and combinatorial in frequency and power dimension. The second proposed auction is fully combinatorial. Simulations results are also provided showing effectiveness of the analyzed auctions (high spectrum utilization ratio) and relation between the players’ satisfaction, their spectrum valuation and varying competition. Finally the guidelines concerning the spectrum auctions in TVWS for the policy makers are proposed.     

Competition and investment — A unified approach

Using a simple but general two-stage framework, this paper identifies the circumstances under which increasing competition leads to more cost-reducing investments. The framework can, for instance, capture increasing substitutability for different types of oligopoly models or changes from Cournot to Bertrand competition. The paper identifies four transmission mechanisms by which competition affects investment. For a firm with lower initial marginal costs (higher efficiency), a positive effect of competition on investment is more likely. Positive spillovers support a negative effect of competition on investment. The relation between competition and investment is not affected in an unambiguous way by the level of pre-existing competition.     

Narrative approach in business network process research — Implications for theory and methodology

The continuous development of theoretical and methodological approaches provides novel insights into how to conceptualize and empirically study multilayered and multi-actor network processes. This theoretic-methodological article shows how network processes can be conceptualized, and how the narrative approach advances the empirical study of these processes. The study builds an agency-structure meta-framework that conceptualizes the emergence of network processes in terms of interaction between individuals from different network actor organizations. The narrative research approach is put forward to implement the study of network processes into empirical reality. The narrative approach allows capturing the relevant actors, their multiple motives, interests and activities, and the mutual interplay of these elements with the contextual levels, thus providing an essential understanding of various types of network processes.     

What lies behind socio-economic inequalities in obesity in Spain? A decomposition approach

The expansion of obesity stands as a major food related health concern arguably driven by a socio-economic vector. However, alongside its prevalence, still scant evidence has examined on the underlying factors that explain the emergence socio-economic inequalities in obesity. This paper makes use of evidence form Spain to empirically address the hypothesis of the existence of income-related inequalities in the probability of suffering obesity in Spain using data from 2003. Besides quantifying inequalities, we take advantage of a concentration index methodology that allows a decomposition of the cross-section explanatory factors. Our findings provide suggestive evidence of significant socio-economic inequalities in the probability of being obese in Spain. However, in decomposing such inequalities we find that education attainment and other demographic covariates appear to have a prominent influence. Hence, rather than the so-called pure “income effect”, we conclude that socio-economic inequalities in obesity result from the additional influence of other confounding – observed and unobserved-effects.     

A hybrid approach based on the variable neighborhood search and particle swarm optimization for parallel machine scheduling problems—A case study for solar cell industry

This paper studies a solar cell industry scheduling problem which is similar to the traditional hybrid flow shop scheduling (HFS). In a typical HFS with parallel machines problem, the allocation of machine resources for each order should be scheduled in advance and then the optimal multiprocessor task scheduling in each stage could be determined. However, the challenge in solar cell manufacturing is the number of machines can be dynamically adjusted to complete the job within the shortest possible time. Therefore, the paper addresses a multi-stage HFS scheduling problem with characteristics of parallel processing, dedicated machines, sequence-independent setup time, and sequence-dependent setup time. The objective is to schedule the job production sequence, number of sublots, and dynamically allocate sublots to parallel machines such that the makespan time is minimized. The problem is formulated as a mixed integer linear programming (MILP) model. A hybrid approach based on the variable neighborhood search and particle swarm optimization (VNPSO) is developed to obtain the near-optimal solution. Preliminary computational study indicates that the developed VNPSO not only provides good quality solutions within a reasonable amount of time but also outperforms the classic branch and bound method and the current industry heuristic practiced by the case company.     

Practice before theory? An approach for testing sequencing effects in pedagogical design

Engineering is a practical discipline, dedicated to the solution of problems through the sound application of principles derived from the natural sciences and mathematics. Engineering pedagogy has therefore to balance the need for learners to gain a deep understanding of the theoretical basis of the problem domain whilst grasping its practical implications. However, little is known as to the most effective sequence of delivery: is it better to begin with theory and build up to practice or vice versa? Here, we present the idea of testing this through a carefully designed pedagogical experiment. We begin by discussing the issues around the creation of a pedagogical experiment to answer such a question, and define the nature and scope of such experiments. We then create a formal framework within which such questions can be tested and present an experiment in the domain of architectural engineering that pilots this new approach. Finally, we discuss the utility of using such a framework to lead evidence-based discussions of pedagogical practice within the engineering education literature, and conclude that similar experiments could be, and should be, completed by other teams wanting to examine delivery order or other binary choice situations.

     

What is the irrigation potential for Africa? A combined biophysical and socioeconomic approach

Although irrigation in Africa has the potential to boost agricultural productivities by at least 50%, food production on the continent is almost entirely rainfed. The area equipped for irrigation, currently slightly more than 13 million hectares, makes up just 6% of the total cultivated area. More than 70% of Africa’s poor live in rural areas and mostly depend on agriculture for their livelihoods. As a result, agricultural development is key to ending poverty on the continent. Many development organizations have recently proposed to significantly increase investments in irrigation in the region. However, the potential for irrigation investments in Africa is highly dependent upon geographic, hydrologic, agronomic, and economic factors that need to be taken into account when assessing the long-term viability and sustainability of planned projects. This paper analyzes the large, dam-based and small-scale irrigation investment potential in Africa based on agronomic, hydrologic, and economic factors. We find significant profitable irrigation potential for both small-scale and large-scale systems. This type of regional analysis can guide distribution of investment funds across countries and should be a first step prior to in-depth country- and local-level assessment of irrigation potential, which will be important to agricultural and economic development in Africa.     

A sufficient statistics approach for welfare analysis of oligopolistic third‐degree price discrimination

This paper proposes a sufficient statistics approach to studying the welfare effects of third-degree price discrimination in differentiated oligopoly. Specifically, our sufficient conditions for price discrimination to increase or decrease social welfare simply entail a cross-market comparison of multiplications of such sufficient statistics as pass-through, conduct, and profit margin that are functions of first-order and second-order elasticities of the firm’s demand. Notably, these results are derived under a general class of market demand, and can be readily extended to accommodate heterogeneous firms. These features suggest that our approach has potential for conducting welfare analysis without a full specification of an oligopoly model.     

Power in distribution channels — Supplier assortment strategy for balancing power

This paper focuses on the move from buyer dominance toward interdependence between buyers and suppliers in a distribution channel. The paper introduces a case study collected through in-depth interviews and participative observations. It examines the relationships between a timber supplier and its customers in the builders' merchants sector. We stress the relevance of considering actions intended to change the power balance, rather than focusing only on trust. The power balance in a dyadic relationship is dynamic, and power positions need to be constantly re-evaluated. An important power resource is information asymmetry, manifested in the supplier's information about: products, regional and local demand, and the usage of the products. For practitioners, we highlight the possibility of exerting a non-coercive power resource, such as information asymmetry, in order to increase the relative power. Furthermore, being open about the power position between a buyer and a seller can foster a more efficient collaboration.     

Social media as a useful tool in food risk and benefit communication? A strategic orientation approach

Although considerable progress has been made in understanding the determinants of risk perception and in identifying the necessary components of effective food risk and benefit communication, this has not been matched with the development of efficient and appropriate communication tools. Little work has been done examining the implications of the explosion of new media and web technologies, which may offer potential for improving food risk and benefit communication. First, this study examines the views of stakeholders (n = 38) and experts (n = 33) in the food domain on the potential use of these emerging media for food risk/benefit communication. Based on in-depth interviews in six European countries (Belgium, Ireland, Italy, Latvia, Spain and The Netherlands), strengths, weaknesses, opportunities and threats (SWOT) of social media in food risk and benefit communication were identified. Second, a Strategic Orientation Round (SOR) was used to evaluate the relative importance of the SWOT components according to stakeholders (n = 10) and experts (n = 13). Results show that both stakeholders and experts confirm a future role of social media in food risk and benefit communication. Strengths as speed, accessibility and interaction make social media an interesting tool in crisis communication or issue awareness raising. Weaknesses as the lack of a filter, low trust, the risk of information overload and a communication preference for traditional media are acknowledged.     

Regional differences in business ethics in the People’s Republic of China: A multi-dimensional approach to the effects of modernisation

This paper investigates the influence of modernisation on the moral judgements of 211 managers in the People’s Republic of China, based on their responses to a series of vignettes depicting potentially unethical behaviour in organisations. Since modernisation can take many forms, this paper takes a multi dimensional approach to examining levels of modernisation in different provinces in China. Three different measures are used, believed to represent different aspects of the modernisation process. These include the level of industrialisation of various provinces, the level of marketisation, or progress toward a market-based economy, and a new measure of Westernisation, or the extent to which individuals adopt aspects of Western lifestyle and materialism. This latter measure is developed and tested in the present study. Statistically significant associations between these three measures of modernisation and managers’ moral judgements were observed and the implications of these findings are discussed.     

Who's going to provide the funding for high tech start‐ups? A model for the analysis of determinants with a fuzzy approach

The aim of this paper is to understand which factors influence the financial structure of Italian young, high‐tech, innovative firms, and to attempt to formulate a predictive model to determine the ideal financial strategy for a given entrepreneurial project. Venture capital is the most relevant form of financing for high‐technology start‐ups in the United States and is frequently cited as crucial in the technological leadership of the US economy. However, banks are also moving toward establishing a role in capital provision, making innovative offers to meet the financial needs of start‐ups, especially in bank‐centric countries such as Italy. Is it possible to build a robust and ordered set of determinants of the financial strategy of new technology‐based firms? Is it possible to gather them in a model that allows a rigorous analysis? Is it possible to summarize the analysis in a synthetic value of orientation to one or other form of financing? Through a systematic review of the literature and comparison between investors, we have taken the first step toward answering these questions. This work develops a methodology to solve the problem and builds a provisional fuzzy‐set based tool to permit the rationalization of the relevant information and effectively support the reduction of qualitative evaluation of complex phenomena into simple and measurable dimensions. The structure of the model is hierarchical but simple. We consider, as the first level of main determinants (sub‐dimensions), the figure of the entrepreneur, the nature of the project, the financial scenario, and the market characteristics. For each of these, we provide deep insights about their relation with finance. We have verified the value of this approach in the context of ten business cases, by matching the financial strategies undertaken by entrepreneurs and the obtainable conclusions with the fuzzy tool. However, the definition of a robust, predictive model requires more consistent empirical validation, which we intend to develop from this work.     

Commercialisation: A meta-approach for agricultural development among smallholder farmers in Africa?

This paper presents a critique of commercialising smallholder farming for agriculture in Sub-Saharan Africa. First it questions the validity of an overarching ‘metanarrative’ approach to development. Then it discusses the different types of knowledge, values and method and draws attention to the increasingly heterogeneous development policy context and also the heterogeneity among the smallholder ‘targets’ of agrifood policies.Second, a case study exemplifies this critique in the context of an existing multistakeholder strategy of commercialising the Zambian cassava sector. Although limited in scope, the primary research illustrates how a commercial supply response should not be assumed from within a rural sector more concerned with food security.The study casts doubt on the validity of a commercialising metanarrative. Rather, it endorses the need for a multidisciplinary understanding of the particular and local context which influences knowledge generation and development design, accounting for different value systems and perceptions of reality and smallholder farmer decision making within heterogeneous contexts.     

A double‐edged sword?: a critical evaluation of the mobile phone in creating work–life balance

This article provides a critical review of the literature on the impact of mobile telephony on work–life balance (WLB). In particular, it focuses on their theoretical frameworks, the nature of the research questions, the methodological choices adopted and the research findings of empirical articles published internationally between 1998 and 2014. This research field is at the crossroads of two theoretical and empirical traditions, and can be characterised by diversity in terms of conceptualisation and operationalisation of measures, which burdens comparisons between findings. Four problems arise with the literature: (1) the consistency and transparency of the theoretical bases they employ; (2) a tendency to technological determinism and to diminish the impact of human choices; (3) difficulty with handling the complexity of factors; and (4) issues with finding sampling strategies that do not restrict the ability to generalise and/or result in omission of specific populations.     

A behavioral approach to strategy—what's the alternative?

The strategy field has generally been viewed as somewhat fragmented with the primary ‘fault line’ stemming from the divide between economic and behavioral approaches. It is argued here that this is a false divide as any but the most trivial problems require a behavioral act of representation prior to invoking a deductive, ‘rational’ approach. In this sense, all approaches are behavioral. Once we recognize rationality as a process, then the pragmatic question becomes which among the imperfect mechanisms to guide choice and behavior may be more or less preferred. Such a viewpoint not only serves to help span the chasm of behavioral and economic approaches, but it may also connect the applied normative frameworks and approaches within the field to more theoretically grounded approaches. Copyright © 2011 John Wiley & Sons, Ltd.     

How to use instrumental variables in addressing endogeneity? A step-by-step procedure for non-specialists

Endogeneity issues in empirical research have received increasing academic attention. Tackling endogeneity problems effectively and using the appropriate estimation techniques are important quality benchmarks in the publication process of many academic journals. In this paper, we discuss the use of instrumental variables (IVs) in business and marketing research, with a particular focus on its implementation in STATA. We discuss several pre- and postestimation tests that researchers can use to implement various versions of IVs in STATA, including two-stage least squares regression, limited information maximum likelihood estimation, and generalized method of moments.     

Managing relationships with public officials — A case of foreign MNCs in Russia

Relationships between business firms and public sector actors are raising an increasing scholarly interest, and they play a critical role for business in the emerging markets. Public officials, as executors of state laws and regulations, are important public actors, but we know little about firms' interaction with them. This study examines how foreign MNCs with an established position in Russia deal with public officials in practice. Public–private net is developed as an analytic tool and applied in an empirical investigation of two Finnish MNCs with operations in Russia. The study focuses on daily activities of managers when interacting with Russian public officials. It reveals a complex structure of public–private nets: on-going interaction relationships involve several MNC units and various Russian public officials. Firms maintain several simultaneous relationships with public officials. Furthermore, they also rely on intermediaries and may build indirect relationships to create some distance to public officials. The results show that relationships with public officials carry an important supportive role in business, and the relationships are mainly used for mutual information exchange.     

Buyer and supplier attractiveness in a strategic relationship — A dyadic multiple-case study

In a strategic buyer–supplier relationship (BSR), both the buyer and the supplier aim to leverage the relationship for gaining competitive advantage. Since strategic BSR requires a lot of effort from both parties, firms have become very selective in terms of with whom they engage in a strategic BSR. Therefore, both buyers and suppliers must shape their attractiveness in order to get the other party to put effort to the relationship. Towards this end, the present study explores the drivers of buyer and supplier attractiveness in strategic relationship through 43 interviews in six buyer–supplier dyads. We identified four main categories of both buyer and supplier attractiveness: 1) economic-based, 2) behavior-based, 3) resource-based, and 4) bridging-based attractiveness. We find economic- and behavior-based attractiveness strongly present in all dyads, while resource- and bridging-based attractiveness are emphasized when the strategic intent has more explorative elements and when the aim is to leverage the dyadic relationship in developing businesses outside the dyad. We synthesize our results to a model of attractiveness in a strategic BSR, which bring forth dyad considerations of buyer and supplier attraction.     

A ‘Knowledge Trading Game’ for collaborative design learning in an architectural design studio

Knowledge-sharing and resource exchange are the key to the success of collaborative design learning. In an architectural design studio, design knowledge entails learning efforts that need to accumulate and recombine dispersed and complementary pieces of knowledge. In this research, firstly, ‘Knowledge Trading Game’ is proposed to be a way for promoting students’ design knowledge exchange, dissemination and refinement. Twelve students are randomly chosen as experimental participants. And secondly, ‘virtual value’ is used for students to trade their design knowledge. In this game, students buy others’ design knowledge to extend their design problem space; students decrease their design solution space through their sold design knowledge. Finally, ‘protocol analysis’ is adapted as the research methodology to examine the results of implementation. A positive outcome is identified that Knowledge Trading Game encourages collaborative design learning.     

Welfare impacts of improved chickpea adoption: A pathway for rural development in Ethiopia?

We analyse the impact of improved chickpea adoption on welfare in Ethiopia using three rounds of panel data. First, we estimate the determinants of improved chickpea adoption using a double hurdle model. We apply a control function approach with correlated random effects to control for possible endogeneity resulting from access to improved seed and technology transfer activities. To instrument for these variables we develop novel distance weighted measures of a household’s neighbours’ access to improved seed and technology transfer activities. Second, we estimate the impact of area under improved chickpea cultivation on household income and poverty. We apply a fixed effects instrumental variables approach where we use the predicted area under cultivation from the double hurdle model as an instrument for observed area under cultivation. We find that improved chickpea adoption significantly increases household income while also reducing household poverty. Finally, we disaggregate results by landholding to explore whether the impact of adoption has heterogeneous effects. Adoption favoured all but the largest landholders, for who the new technology did not have a significant impact on income. Overall, increasing access to improved chickpea appears a promising pathway for rural development in Ethiopia’s chickpea growing regions.