5,884 research outputs found

    Reliability analysis of reconstructing phylogenies under long branch attraction conditions

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    Master's Project (M.S.) University of Alaska Fairbanks, 2018.In this simulation study we examined the reliability of three phylogenetic reconstruction techniques in a long branch attraction (LBA) situation: Maximum Parsimony (M P), Neighbor Joining (NJ), and Maximum Likelihood. Data were simulated under five DNA substitution models-JC, K2P, F81, HKY, and G T R-from four different taxa. Two branch length parameters of four taxon trees ranging from 0.05 to 0.75 with an increment of 0.02 were used to simulate DNA data under each model. For each model we simulated DNA sequences with 100, 250, 500 and 1000 sites with 100 replicates. When we have enough data the maximum likelihood technique is the most reliable of the three methods examined in this study for reconstructing phylogenies under LBA conditions. We also find that MP is the most sensitive to LBA conditions and that Neighbor Joining performs well under LBA conditions compared to MP

    Constant temperature description of the nuclear level densities

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    The spin and parity dependent nuclear level densities (NLD) are calculated for medium-heavy nuclei using shell model techniques. The NLD are used to calculate cross sections and reaction rates of interest for nuclear astrophysics and nuclear energy applications. We investigate a new approach of describing the shell model NLD via a constant temperature parametrization. This approach provides new information about the effects of symmetries on the temperature of the low-lying nuclear states, and it is shown to be more versatile for applications

    Venture idea newness, relatedness and performance in nascent ventures

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    Principal Topic The study of the origin and characteristics of venture ideas - or ''opportunities'' as they are often called - and their contextual fit are key research goals in entrepreneurship (Davidsson, 2004). We define venture idea as ''the core ideas of an entrepreneur about what to sell, how to sell, whom to sell and how an entrepreneur acquire or produce the product or service which he/she sells'' for the purpose of this study. When realized the venture idea becomes a ''business model''. Even though venture ideas are central to entrepreneurship yet its characteristics and their effect to the entrepreneurial process is mysterious. According to Schumpeter (1934) entrepreneurs could creatively destruct the existing market condition by introducing new product/service, new production methods, new markets, and new sources of supply and reorganization of industries. The introduction, development and use of new ideas are generally called as ''innovation'' (Damanpour & Wischnevsky, 2006) and ''newness'' is a property of innovation and is a relative term which means that the degree of unfamiliarity of venture idea either to a firm or to a market. However Schumpeter's (1934) discusses five different types of newness, indicating that type of newness is an important issue. More recently, Shane and Venkataraman (2000) called for research taking into consideration not only the variation of characteristics of individuals but also heterogeneity of venture ideas, Empirically, Samuelson (2001, 2004) investigated process differences between innovative venture ideas and imitative venture ideas. However, he used only a crude dichotomy regarding the venture idea newness. According to Davidsson, (2004) as entrepreneurs could introduce new economic activities ranging from pure imitation to being new to the entire world market, highlighting that newness is a matter of degree. Dahlqvist (2007) examined the venture idea newness and made and attempt at more refined assessment of the degree and type of newness of venture idea. Building on these predecessors our study refines the assessment of venture idea newness by measuring the degree of venture idea newness (new to the world, new to the market, substantially improved while not entirely new, and imitation) for four different types of newness (product/service, method of production, method of promotion, and customer/target market). We then related type and degree of newness to the pace of progress in nascent venturing process. We hypothesize that newness will slow down the business creation process. Shane & Venkataraman (2000) introduced entrepreneurship as the nexus of opportunities and individuals. In line with this some scholars has investigated the relationship between individuals and opportunities. For example Shane (2000) investigates the relatedness between individuals' prior knowledge and identification of opportunities. Shepherd & DeTinne (2005) identified that there is a positive relationship between potential financial reward and the identification of innovative venture ideas. Sarasvathy's 'Effectuation Theory'' assumes high degree of relatedness with founders' skills, knowledge and resources in the selection of venture ideas. However entrepreneurship literature is scant with analyses of how this relatedness affects to the progress of venturing process. Therefore, we assess the venture ideas' degree of relatedness to prior knowledge and resources, and relate these, too, to the pace of progress in nascent venturing process. We hypothesize that relatedness will increase the speed of business creation. Methodology For this study we will compare early findings from data collected through the Comprehensive Australian Study of Entrepreneurial Emergence (CAUSEE). CAUSEE is a longitudinal study whose primary objective is to uncover the factors that initiate, hinder and facilitate the process of emergence and development of new firms. Data were collected from a representative sample of some 30,000 households in Australia using random digit dialing (RDD) telephone survey interviews. Through the first round of data collection identified 600 entrepreneurs who are currently involved in the business start-up process. The unit of the analysis is the emerging venture, with the respondent acting as its spokesperson. The study methodology allows researchers to identify ventures in early stages of creation and to longitudinally follow their progression through data collection periods over time. Our measures of newness build on previous work by Dahlqvist (2007). Our adapted version was developed over two pre-tests with about 80 participants in each. The measures of relatedness were developed through the two rounds of pre-testing. The pace of progress in the venture creation process is assessed with the help of time-stamped gestation activities; a technique developed in the Panel Study of Entrepreneurial Dynamics (PSED). Results and Implications We hypothesized that venture idea newness slows down the venturing process whereas relatedness facilitates the venturing process. Results of 600 nascent entrepreneurs in Australia indicated that there is marginal support for the hypothesis that relatedness assists the gestation progress. Newness is significant but is the opposite sign to the hypothesized. The results give number of implications for researchers, business founders, consultants and policy makers in terms of better knowledge of the venture creation process

    Understanding venture idea newness, relatedness and change among nascent and young entrepreneurs

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    The entrepreneurial process involves all the functions, activities, and actions associated with the perception of opportunities and the creation of the organizations to pursue these opportunities (cf. Key, Foo and Lim, 2002). Shane and Venkataraman (2000) introduced entrepreneurship as a nexus between the opportunity and entrepreneurial individuals. Thus, opportunities are an important part and central to the entrepreneurial process. Following Davidsson (2003) we here use the concept ''venture idea'' rather than ''opportunities''. Venture ideas are ideas for new products or services or bundles; introducing new price/value relations; imitative entry and entering new markets (Davidsson, 2003). This implies that venture ideas are the core ideas of an entrepreneur about what to sell, how to sell, whom to sell and how an entrepreneur acquire or produce the product or service which he/she sells. Timmons (1994) states that the finding a good idea is the first step in the task of converting an entrepreneur's creativity in to an opportunity. Explaining the development of venture ideas or - as they are often called - 'opportunities' is regarded as a key research goal in entrepreneurship (Davidsson, Hunter and Klofsten, 2006). For example, since the ideas have differentiating effects on the discovery and exploitation processes as well as on profitability and potential market impact the identifying and selecting the right venture ideas for new businesses are among the most important abilities of a successful entrepreneur (Ardichvili, Cardozo and Ray, 2003) Even though the opportunity, its recognition and exploitation have been extensively discussed and researched among researchers around the world (Bhave, 1994; Casson, 1982; Davidsson, 2003; Kirzner, 1973; Sarsvathy, Dew, Ramakrishna & Venkataraman, 2003; Shane, 2000; Shane & Venkataraman, 2000; Venkataraman,1997) there is a scarcity of research carried out on the characteristics of those opportunities and how such characteristics affect, e.g., firm performance , growth or survival. The importance of investigating such questions is exemplified by Samuelsson (2004), who found that the gestation process and its determinants were vastly different for innovative vs. imitative ventures. In this research we investigate how three aspects of venture ideas affect the pace at which progress is made in the venture creation process. Bhave (1994) argues that the venture creation process is more complex or difficult for novel business ideas. For this reason we assess and estimate the effects of four aspects of newness: the procuct/service itself; the method for promotion and selling; the methods for producing or sourcing, and newness in terms what markets or customers are served or targeted. Shane (2000) demonstrated that prior knowledge of the founders is an important factor in venture development. Similarly, Sarasvathy's (2001) Effectuation Theory proposes a high degree of relatedness with founders' knowledge and means. Hence, we assess and estimate the effects of the degree of alignment of the venture ideas with the prior knowledge and skills of the founders as well as with the financial, physical and other resources they had access to. Further, since entrepreneurs operate in an environment of heterogeneous and uncertain, they have to change their original business ideas time to time (Davidsson, Hunter, Klofsten, 2006). Presumably, changes of the venture idea could either facilitate or complicate the gestation process. In order to explore this we also assess and estimate the effect of the extent of change of the business idea that have been made. We investigate this for the same four aspects as for which we assess newness. Methodology/Key Propositions For this study we will compare early findings from data collected through the CAUSEE. CAUSEE is a longitudinal study whose primary objective is to describe how new venture come into existence. Data was collected from a representative sample of some 25,000 households in Australia using random digit dialling (RDD) telephone survey interviews. Included in the study are the approximately 600 cases where the respondent is currently involved in a business start-up, and another 600 who are owners of an up-and-running firm started in the last three years, in both cases where the respondent is also willing to participate in the study. The unit of the analysis is the emerging venture, with the respondent acting as its spokesperson. The study methodology allows researchers to identify ventures in early stages of creation and to longitudinally follow their progression through data collection periods over time. Our measures of newness build on previous work by Dahlqvist (2007). Our adapted version was developed over two pre-tests with about 80 participants in each. The measures of relatedness and change were newly developed through the two rounds of pre-testing. The pace of progress in the venture creation process is assessed with the help of time-stamped gestation activities; a technique developed in the Panel Study of Entrepreneurial Dynamics (PSED) (see Gartner et al., 2004). Results and Implications Data collection is under way at the time of this writing. The results will help develop better knowledge of the venture creation process and its success factors, enabling better theory as well as more adequate dissemination of practical advice through teaching and consultancy

    Effect of promoting country of origin as an ethnocentric appeal in developing local brands: special reference to telecommunication industry of Sri Lanka

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    Sri Lanka is emerging as service sector driven economy with the GDP penetration of 50%-60% from service sector. After imposing the open economy policy in 1977, local brands had to gear ahead with intensive competition came from international brands. Telecommunication industry of Sri Lanka has been dominated by international brands, but local brands are strategically promoting the concept of country of origin (CO) or being local as a motive for citizens to deliberately purchase locally originated brands. In this context researchers viewed this branding practice, and selected 200 respondents from four geographical areas under the stratified probability sampling method to investigate the effect of country of origin in terms of brand performance. Both descriptive and inferential statistical analysis executed by PCA (principal component analysis) factor analysis accompanied with testing two hypotheses revealed that Country of Origin (CO) or promoting as being local had impacted less significantly on brand awareness and recalled power development of telecommunication brands against the competitive foreign brands. However, it has a significant impact on brand recalling power.Country of origin, ethnocentrism, local brands, telecommunication., Consumer/Household Economics, D12, L96,

    Guide to on-site wastewater management for industrial and commercial establishments and other institutions: guide for vehicle service station owners and managers

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    Wastewater treatment, Environmental management, Organizations, Environmental Economics and Policy, Industrial Organization,
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