135 research outputs found
Predicting new venture survival and growth: does the fog lift?
This paper investigates whether new venture performance becomes easier to predict as the venture ages: does the fog lift? To address this question we primarily draw upon a theoretical framework, initially formulated in a managerial context by Levinthal (Adm Sci Q 36(3):397–420, 1991) that sees new venture sales as a random walk but survival being determined by the stock of available resources (proxied by size). We derive theoretical predictions that are tested with a 10-year cohort of 6579 UK new ventures in the UK. We observe that our ability to predict firm growth deteriorates in the years after entry—in terms of the selection environment, the ‘fog’ seems to thicken. However, our survival predictions improve with time—implying that the ‘fog’ does lift
Use of knowledge-based restraints in phenix.refine to improve macromolecular refinement at low resolution
Recent developments in PHENIX are reported that allow the use of reference-model torsion restraints, secondary-structure hydrogen-bond restraints and Ramachandran restraints for improved macromolecular refinement in phenix.refine at low resolution
MolProbity: all-atom structure validation for macromolecular crystallography
MolProbity structure validation will diagnose most local errors in macromolecular crystal structures and help to guide their correction
Graphical tools for macromolecular crystallography in PHENIX.
A new Python-based graphical user interface for the PHENIX suite of crystallography software is described. This interface unifies the command-line programs and their graphical displays, simplifying the development of new interfaces and avoiding duplication of function. With careful design, graphical interfaces can be displayed automatically, instead of being manually constructed. The resulting package is easily maintained and extended as new programs are added or modified
All grown up? The fate after 15 years of a quarter of a million UK firms born in 1998
The theory of firm growth is in a rather unsatisfactory state. However, the analysis of large firm-level datasets which have become available in recent years allows us to begin building an evidence base which can, in turn, be used to underpin the development of more satisfactory theory. Here we study the 239 thousand UK private sector firms born in 1998 over their first 15 years of life. A first, and quite striking, finding is the extraordinary force of mortality. By age 15, 90% of the UK firms born in 1998 are dead, and, for those surviving to age 15, the hazard of death is still about 10% a year. The chance of death is related to the size and growth of firms in an interesting way. Whilst the hazard rate after 15 years is largely independent of size at birth, it is strongly affected by the current (age 14) size. In particular, firms with more than five employees are half as likely to die in the next year as firms with less than five employees. A second important finding is that most firms, even those which survive to age 15, do not grow very much. By age 15 more than half the 26,000 survivors still have less than five jobs. In other words, the growth paths – what we call the ‘growth trajectories’ – of most of the 26,000 survivors are pretty flat. However, of the firms that do grow, firms born smaller grow faster than those born larger. Another striking finding is that growth is heavily concentrated in the first five years. Whilst growth does continue, even up to age 15, each year after age five it involves only a relatively small proportion of firms. Finally, there are two groups of survivors which contribute importantly to job creation. Some are those born relatively large (with more than 20 jobs) although their growth rate is quite modest. More striking though, is a very small group of firms born very small with less than five jobs (about 5% of all survivors) which contribute a substantial proportion (more than one third) of the jobs added to the cohort total by age 15
phenix.model_vs_data: a high-level tool for the calculation of crystallographic model and data statistics
Application of phenix.model_vs_data to the contents of the Protein Data Bank shows that the vast majority of deposited structures can be automatically analyzed to reproduce the reported quality statistics. However, the small fraction of structures that elude automated re-analysis highlight areas where new software developments can help retain valuable information for future analysis
PHENIX: a comprehensive Python-based system for macromolecular structure solution.
Macromolecular X-ray crystallography is routinely applied to understand biological processes at a molecular level. However, significant time and effort are still required to solve and complete many of these structures because of the need for manual interpretation of complex numerical data using many software packages and the repeated use of interactive three-dimensional graphics. PHENIX has been developed to provide a comprehensive system for macromolecular crystallographic structure solution with an emphasis on the automation of all procedures. This has relied on the development of algorithms that minimize or eliminate subjective input, the development of algorithms that automate procedures that are traditionally performed by hand and, finally, the development of a framework that allows a tight integration between the algorithms
Inspired or foolhardy: sensemaking, confidence and entrepreneurs' decision-making.
The purpose of this paper is to investigate the role of confidence in how both new and experienced entrepreneurs interpret and make sense of their business environment to inform decision-making. We illustrate our conceptual arguments with descriptive results from a large-scale (n = 6289) survey on entrepreneurs' perception of business performance and their decisions taken at a time of uncertainty in an economic downturn. Quantitative findings are stratified along experiential lines to explore heterogeneity in entrepreneurial decision-making and directly inform our conceptual arguments, while qualitative data from open questions are used to explain the role of confidence. Newer entrepreneurs are found to be more optimistic in the face of environmental risk, which impacts on their decision-making and innovative capabilities. However, the more experienced entrepreneurs warily maintain margin and restructure to adapt to environmental changes. Instead of looking directly at the confidence of individuals, we show how confidence impacts sensemaking, and ultimately, decision-making. These insights inform research on the behaviour of novice and experienced entrepreneurs in relation to innovative business activities. Specifically, blanket assumptions on the role of confidence may be misplaced as its impact changes with experience to alter how entrepreneurs make sense of their environment
'I Want to, But I Also Need to' - Start-Ups Resulting from Opportunity and Necessity
When unemployed persons go into business, they often are characterized as necessity entrepreneurs, because push factors, namely their unemployment, likely prompted their decision. In contrast to this, business founders who have been previously employed represent opportunity entrepreneurs because pull factors provide the rationale for their decision. However, a data set of nearly 1,900 business start-ups by unemployed persons reveals that both kind of motivation can be observed among these start-ups. Moreover, a new type of entrepreneur emerges, motivated by both push and pull variables simultaneously. An analysis of the development of the businesses reflecting three different motivational types indicates a strong relationship between motives, survival rates and entrepreneurial development. We find in particular that start-ups out of opportunity and necessity have higher survival rates than do start-ups out of necessity, even if both types face the same duration of previous unemployment
"Segurando na mão de Deus": organizações religiosas e apoio ao empreendedorismo
The article investigates mechanisms offered by religious organizations to support entrepreneurial initiatives. We examine two organizations, one catholic and one protestant, using a qualitative case study design. The comparative assessment was based on three dimensions of support that appeared as a result of the data analysis, that we called spaces of information, formation, and motivation. The dimensions are considered as possible important research results and were used to investigate the impact on the traditional stages of the entrepreneurial process of the mechanisms made available by the two religious organizations. The analysis indicates certain similarities between the two cases: church membership assists in the creation of social capital that impacts various economic dimensions, as well as provides religious support to the economic motivations. However, the differences between the two churches become evident in the religious interpretation of economic success and in the articulation and closure of their social networks.Este artigo investiga mecanismos de apoio ao empreendedorismo proporcionados por organizações religiosas. Foram pesquisadas duas organizações, uma católica e outra evangélica, por meio de estudo de caso qualitativo. A análise comparativa baseou-se em três dimensões específicas do apoio ao empreendedorismo que emergiram na própria pesquisa de campo e que denominamos espaços de informação, formação e motivação. Consideramos tais dimensões como importantes achados desta pesquisa e as utilizamos como categorias para investigar o impacto dos mecanismos oferecidos pelas organizações religiosas nas etapas do processo de empreendedorismo. Os resultados do trabalho indicam uma confluência entre os dois casos: o pertencimento às igrejas resulta na formação de capital social orientado para as várias dimensões econômicas e no reforço religioso à motivação econômica. As diferenças, contudo, encontram-se na representação religiosa do significado do sucesso econômico e na articulação e fechamento de suas respectivas redes sociais.Este artículo investiga los mecanismos de apoyo al emprendedorismo proporcionados por organizaciones religiosas. Fueron investigadas dos organizaciones, una católica y otra evangélica, por medio de un estudio de caso cualitativo. El análisis comparativo se basó en tres dimensiones específicas del apoyo al emprendedorismo que emergieron en el mismo estudio de campo y que denominamos espacios de información, formación y motivación. Consideramos tales dimensiones como importantes hallazgos de esta investigación y las utilizamos como categorías para investigar el impacto de los mecanismos ofrecidos por las organizaciones religiosas en las etapas del proceso de emprendedorismo. Los resultados del trabajo indican una confluencia entre los dos casos: la pertenencia a las iglesias resulta en la formación de capital social orientado hacia las varias dimensiones económicas y en el refuerzo religioso a la motivación económica. Las diferencias, no obstante, se encuentran en la representación religiosa del significado del éxito económico y en la articulación y closure de sus respectivas redes sociales
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