An empirical mixed model to quantify climate influence on the growth of Pinus halepensis Mill. stands in South-Eastern Spain

The influence of climate on forest stand composition, development and growth is undeniable. Many studies have tried to quantify the effect of climatic variables on forest growth and yield. These works become especially important because there is a need to predict the effects of climate change on the development of forest ecosystems. One of the ways of facing this problem is the inclusion of climatic variables into the classic empirical growth models. The work has a double objective: (i) to identify the indicators which best describe the effect of climate on Pinus halepensis growth and (ii) to quantify such effect in several scenarios of rainfall decrease which are likely to occur in the Mediterranean area. A growth mixed model for P. halepensis including climatic variables is presented in this work. Growth estimates are based on data from the Spanish National Forest Inventory (SNFI). The best results are obtained for the indices including rainfall, or rainfall and temperature together, with annual precipitation, precipitation effectiveness, Emberger?s index or free bioclimatic intensity standing out among them. The final model includes Emberger?s index, free bioclimatic intensity and interactions between competition and climate indices. The results obtained show that a rainfall decrease about 5% leads to a decrease in volume growth of 5.5?7.5% depending on site quality.

Examining the Impact of Child Psychologists' Stigmatization of Parents on Treatment Outcomes Through a Developmental Lens

The purpose of this paper is to examine how child psychologists' specialized training inhuman development may make them more prone to stigmatize the parents of their young clients. The stigmatization of parents may lead to fewer parents seeking treatment for their children and to poorer treatment outcomes for those who work with a child psychologist. The process of stigmatization is summarized to provide context for the method through which parents receive stigma. A commonly used theory of child development, Erik Erikson's stages of ego development, is outlined to provide background on how child psychologists may interpret and evaluate a child'sdevelopment. Child psychologists' may identify parenting practices that seem to hinder or stunt children's emotional development, which would make the psychologist more aptto stigmatize and isolate parents from the treatment process. To demonstrate the unique ways in which a child psychologist may stigmatize parents of children at different developmental stages two case studies are included. Finally, a theoretical model of treatment is described that may be more inclusive, and less stigmatizing of parents. This model outlines how the parents' concerns about and observations of their children should be validated and reflected in the treatment process. This treatment modality would allow for child psychologists to more actively involve parents in treatment and provide more education and support around their children's unique emotional development needs. Through this treatment model and child psychologists' awareness of and attempts to reduce the stigmatization of parents, treatment outcomes for young clients may improve.

Three essays on self-employment transitions, organizational capital, and firm formation

This dissertation explores how economic, organizational, and personal factors affect self-employment transitions, occupational decisions, and firm formation activities of individuals at different positions in the skill distribution. The first essay of my dissertation studies how local unemployment rates differentially affect entry into self-employment by individuals at different places in the skill distribution. The empirical results show a positive correlation between local unemployment rates and entry into self-employment for low-ability workers, but not for high-ability workers. Including employer size to eliminate possible distortions showed that the positive association between unemployment and self-employment among low-ability workers is in fact driven by the small firm effect. Controlling for firm size yields a negative association between unemployment and self-employment among high-ability workers. Effects of organizational capital, human capital and physical capital, on the firm formation activities of people at distinct skill levels depend on the type of the industry which is chosen for the new firm. Two types of industries, capital-intensive and ability-intensive, are utilized to explore this hypothesis in the second essay. A capital-intensive industry requires more physical investment, and consequently more funds, whereas, an ability-intensive industry requires more human capital. It is shown that high human capital requirements are associated with higher earnings among the most able individuals, and therefore makes them more likely to found firms in an ability-intensive industry. Wealthy people are more likely to establish both capital-intensive and ability-intensive firms, even though the amount of funds necessary for two industry types differs. Moreover, entry into both industries is predicted to happen later in life due to the removal of entry barriers constituted by required investment spending using savings when old. Empirical mixed results are observed. The third essay investigates earning differentials between future entrepreneurs and their non-entrepreneurial colleagues. Results show that high-ability firm-owners in an ability-intensive industry were earning more than those that remained in wage-work, whereas, low-ability firm-owners in a capital-intensive industry were earning less than those remaining in paid-work.

Mixed Public-Private Enterprises in Europe: Economic Theory and an Empirical Analysis of Italian Water Utilities. Bruges European Economic Research (BEER) Papers 4/July 2006

Mixed enterprises, which are entities jointly owned by the public and private sector, are spreading all over Europe in local utilities. Well aware that in the vast majority of cases the preference of local authorities towards such governance structure is determined by practical reasons rather than by the ambition to implement new regulatory designs (an alternative to the typical “external” regulation), our purpose is to confer some scientific value to this phenomenon which has not been sufficiently investigated in the economic literature. This paper aims at proposing an economic analysis of mixed enterprises, especially of the specific configuration in which the public partner acts as controller and the private one (or “industrial” partner) as service provider. We suggest that the public service concession to mixed enterprises could embody, under certain conditions, a noteworthy substitute to the traditional public provision and the concession to totally private enterprises, as it can push regulated operators to outperform and limit the risk of private opportunism. The starting point of the entire analysis is that ownership allows the (public) owner to gather more information about the actual management of the firm, according to property rights theory. Following this stream of research, we conclude that under certain conditions mixed enterprises could significantly reduce asymmetric information between regulators and regulated firms by implementing a sort of “internal” regulation. With more information, in effect, the public authority (as owner/controller of the regulated firm, but also as member of the regulatory agency) can stimulate the private operator to be more efficient and can monitor it more effectively with respect to the fulfilment of contractual obligations (i.e., public service obligations, quality standards, etc.). Moreover, concerning the latter function, the board of directors of the mixed enterprise can be the suitable place where public and private representatives (respectively, welfare and profit maximisers) can meet to solve all disputes arising from incomplete contracts, without recourse to third parties. Finally, taking into account that a disproportionate public intervention in the “private” administration (or an ineffective protection of the general interest) would imply too many drawbacks, we draw some policy implications that make an equitable debate on the board of the firm feasible. Some empirical evidence is taken from the Italian water sector.

Empirical aspects of a mixed method approach to economic network analysis

We discuss the interactions among the various phases of network research design in the context of our current work using Mixed Methods and SNA on networks and rural economic development. We claim that there are very intricate inter-dependencies among the various phases of network research design - from theory and formulation of research questions right through to modes of analysis and interpretation. Through examples drawn from our work we illustrate how choices about methods for Sampling and Data Collection are influenced by these interdependencies.

Managing new product development in the Chinese steel industry: An empirical investigation

This study explores several important aspects of the management of new product development (NPD) in the Chinese steel industry. Specifically it explores NPD success factors, the importance of management functions to new product success and measures of new product success from the perspective of the industry's practitioners. Based on a sample of 190 industrial practitioners from 18 Chinese steel companies, the study provides a mixed picture as China makes the transition from a centrally-controlled to market-based economy. On one hand, respondents ranked understanding users' needs as the most important factor influencing the performance of the new products. Further, formulating new product strategy and strengthening market research are perceived as the most important managerial functions in NPD. However, technical performance measures are regarded as more important and are more widely used in industry than market-based or financial measures of success.

Impact of mobile app user acquisition on managerial decisions: Evidence from empirical experiment

In this research we conducted a mixed research, using qualitative and quantitative analysis to study the relationship and impact between mobile advertisement and mobile app user acquisition and the conclusions companies can derive from it. Data was gathered from management of mobile advertisement campaigns of a portfolio of three different mobile apps. We found that a number of implications can be extracted from this intersection, namely to product development, internationalisation and management of marketing budget. We propose further research on alternative app users sources, impact of revenue on apps and exploitation of product segments: wearable technology and Internet of Things.

Choice of Contracts in the British National Health Service: An Empirical Study

Following major reforms of the British National Health Service (NHS) in 1990, the roles of purchasing and providing health services were separated, with the relationship between purchasers and providers governed by contracts. Using a mixed multinomial logit analysis, we show how this policy shift led to a selection of contracts that is consistent with the predictions of a simple model, based on contract theory, in which the characteristics of the health services being purchased and of the contracting parties influence the choice of contract form. The paper thus provides evidence in support of the practical relevance of theory in understanding health care market reform.

Social influences on fertility : a comparative mixed methods study in eastern and western Germany

This article uses a mixed methods design to investigate the effects of social influence on family formation in a sample of eastern and western German young adults at an early stage of their family formation. Theoretical propositions on the importance of informal interaction for fertility and family behavior are still rarely supported by systematic empirical evidence. Major problems are the correct identification of salient relationships and the comparability of social networks across population subgroups. This article addresses the two issues through a combination of qualitative and quantitative data collection and analysis. In-depth interviewing, network charts, and network grids are used to map individual personal relationships and their influence on family formation decisions. In addition, an analysis of friendship dyads is provided.

Infestation and natural parasitism of aphids in single and mixed pastures of black oats and ryegrass

Some species of aphids are major pests on cereal crops and grass pastures. Usually these pests are not adequately controlled in pasture lands that become sources of aphid infestations to cereal crops. The dynamics of aphids and the incidence of natural enemies are less known in pasture systems than in cereal fields. The objective of this work was to assess the aphid infestation and natural aphid parasitism in different pasture composition. Three hypotheses were tested: 1- the aphid species composition in pastures may vary according to the cereal species in the field; 2- the mixture of two plant species can modify the amount and diversity of aphids; 3- the plant species composition of pasture fields influences the parasitism of aphids. Empirical data were obtained from three Poaceae fields: black oats (Avena strigosa L.), ryegrass (Lolium multiflorum L.), and a mixed field of black oats and ryegrass. The most abundant aphid species was Rhopalosiphum padi followed by Sitobion avenae. Plant species composition increases the amount and the parasitism rates of aphids. The mixture of heavily infested black oats with a poorly infested ryegrass resulted in reduction of aphid infestation in comparison with heavily-infested single plant species field. This is possible because the conditions are favorable for the development of parasitoid populations. Aphidius colemani was the main parasitoid found in these areas.

IFRS and Asymmetrical Information: Empirical Evidence from the Finnish Stock Markets

Tutkimuksen tavoitteena on selvittää kansainvälisiin tilinpäätösstandardeihin siirtymisen vaikutuksia epäsymmetriseen informaatioon Suomen osake-markkinoilla. Suomalaisten tilinpäätöskäytäntöjen ja kansainvälisten standardien eroja on selvitetty ensin laadullisin menetelmin,jonka jälkeen on tehty asymmetrisen informaation markkinapohjaisiin mittareihinperustuva kvantitatiivinen tutkimus. Yleisiin eroavaisuuksiin liittyvän selvityksen lisäksi on tutkittu erikseen erityisesti standardimuutoksen vaikutusta älylliseen pääomaan liittyvään informaation asymmetriaan. Empiirisessä osiossa älyllisen pääoman epäsuoraksi mitaksi on valittu kehitys- ja tutkimusmenojen suhde taseen loppusummaan. Kuten oletus oli, sekä laadullisen että empiirisen osion tulokset viittaavat siihen, että IFRS:n myötä informaatioympäristö on parantunut. Uudet standardit vaativat laajempaa ja tarkempaa informaation julkaisua liittyen älylliseen pääomaan, mikä ei ole kuitenkaan havaittavissa valituissa mittareissa

Empirical models for predicting the production of wild mushrooms in Scots pine (Pinus sylvestris L.) forests in the Central Pyrenees

Mushroom picking has become a widespread autumn recreational activity in the Central Pyrenees and other regions of Spain. Predictive models that relate mushroom production or fungal species richness with forest stand and site characteristics are not available. This study used mushroom production data from 24 Scots pine plots over 3 years to develop a predictive model that could facilitate forest management decisions when comparing silvicultural options in terms of mushroom production. Mixed modelling was used to model the dependence of mushroom production on stand and site factors. The results showed that productions were greatest when stand basal area was approximately 20 m2 ha-1. Increasing elevation and northern aspect increased total mushroom production as well as the production of edible and marketed mushrooms. Increasing slope decreased productions. Marketed Lactarius spp., the most important group collected in the region, showed similar relationships. The annual variation in mushroom production correlated with autumn rainfall. Mushroom species richness was highest when the total production was highest.

Choosing hybrid organizations for local services delivery : An empirical analysis of partial privatization

The empirical literature about factors explaining local government delivery choices has traditionally focused the attention on the public or private production dilemma. However, hybrid organizational forms such as mixed public-private firms are increasingly used in several European countries. This paper makes use of survey data from Spanish municipalities to examine motivations of local governments for engaging in hybrid organizational forms. Data refer to two very relevant local services: water distribution and solid waste collection. The empirical analysis indicates that the use of mixed firms emerge as a type of pragmatically based ‘third way’ between pure public and pure private production. Indeed, local governments make use of mixed firms when cost considerations (scale economies, transaction costs and soon), financial constraints and private interests exert contradictory pressures. On the contrary, political and ideological factors do not play any significant role on the local government decision of engaging or not in joint ventures with private partners.

The use of mixed methods research in the behavioral sciences field

Mixed methods research involves the combined use of quantitative and qualitative methods in the same research study, and it is becoming increasingly important in several scientific areas. The aim of this paper is to review and compare through a mixed methods multiple-case study the application of this methodology in three reputable behavioural science journals: the Journal of Organizational Behavior, Addictive Behaviors and Psicothema. A quantitative analysis was carried out to review all the papers published in these journals during the period 2003-2008 and classify them into two blocks: theoretical and empirical, with the latter being further subdivided into three subtypes (quantitative, qualitative and mixed). A qualitative analysis determined the main characteristics of the mixed methods studies identified, in order to describe in more detail the ways in which the two methods are combined based on their purpose, priority, implementation and research design. From the journals selected, a total of 1.958 articles were analysed, the majority of which corresponded to empirical studies, with only a small number referring to research that used mixed methods. Nonetheless, mixed methods research does appear in all the behavioural science journals studied within the period selected, showing a range of designs, where the sequential equal weight mixed methods research design seems to stand out.

Sulfuric acid - glucose separation using mixed-recycle steady state recycling chromatography

Batch chromatography is a widely used separation technique in a variety of fields meeting difficult separations. Several technologies for improving the performance of chromatography have been studied, including mixed-recycle steady state recycling (MR-SSR) chromatography. Design of MR-SSR has been commonly limited on 100 % purity constraint cases and empirical work. In this study a predictive design method was used to optimize feed pulse size and design a number of experimental MR-SSR separations for a solution of 20 % sulfuric acid and 100 g/L glucose. The design was under target product fraction purities of 98.7 % for H2SO4 and 95 % for glucose. The experiments indicate a maximum of 59 % increase in sulfuric acid productivity and 82 % increase for glucose when compared to corresponding batch separation. Eluent consumption was lowered by approximately 50 % using recycling chromatography. Within this study the target purities and yields set in design were not completely met, and further optimization of the process is deemed necessary.