Necessity and Opportunity Entrepreneurs and their Duration in Self-employment: Evidence from German Micro Data

Using data from the German Socio-Economic Panel Study (GSOEP), we analyze whether necessity entrepreneurs differ from opportunity entrepreneurs in terms of self-employment duration. Using univariate statistics, we find that opportunity entrepreneurs remain in self-employment longer than necessity entrepreneurs. However, after controlling for the entrepreneurs’ education in the professional area where they start their venture, this effect is no longer significant. We therefore conclude that the difference observed is not an original effect but rather is due to selection. We then go on to discuss the implications of our findings for entrepreneurship-policy making, and give suggestions to improve governmental start-up programs

Determinanten des Erfolgs staatlich geförderter Existenzgründungen – eine empirische Untersuchung

Ein Großteil der Neugründungen in Deutschland ist auf staatliche Förderung von Existenzgründern zurückzuführen. Dieser Anteil hat sich nach Einführung des als „Ich-AG“ bekannten Existenzgründungszuschusses Anfang 2003 stark erhöht. Die Erfolgsfaktorenforschung hat diese Form von Gründungen bislang jedoch wenig untersucht. Im Rahmen einer großzahligen Befragung von geförderten Existenzgründern untersucht dieser Beitrag die Erfolgsdeterminanten solcher geförderter Existenzgründungen. Die Ergebnisse der Analyse zeigen, dass der Gewinn aus der Existenzgründung bei älteren Gründern und bei Gründern mit einer langen Phase der Arbeitslosigkeit vor der Gründung seltener beziehungsweise erst später zur Bestreitung des Lebensunterhalts ausreicht. Dies gilt auch für Franchisegründungen und für Gründungen durch Frauen. In Bezug auf Bildungsvariablen, Gründungserfahrung und Teamgründungen im Vergleich zu Einzelgründungen wurde kein Effekt gefunden. Vorhandene Branchenerfahrung wirkt sich hingegen positiv auf den Erfolg der Gründung aus, Gründungs- und Führungserfahrung dagegen nicht. Die Implikationen unserer Ergebnisse für die Entrepreneurship-Forschung sowie für die Entrepreneurship-Praxis werden diskutiert. Herausforderungen aus Sicht der Gründungspolitik werden aufgezeigt.A large number of new ventures in Germany are undertaken due to government aid. With the introduction of the “Ich-AG” or “me-plc” in January 2003, this share has increased strongly. Entrepreneurship research so far has said very little about the success and the determinants of success of these types of start-ups. With this study, we aim to close this gap. We analyze the success and the determinants of success of these new ventures in a large scale survey of founders that have received governmental aid for their start-up. Our results show that the income generated by the venture is less likely to cover the costs of living in particular for elderly founders and for those founders that have experienced a long period of unemployment before they started their venture. This finding is also true for new ventures founded by women as well as for franchise start-ups. As concerns formal education, founder experience, and the fact whether the venture is founded by a team or not no significant effects exist. Industry experience, however, has a significant positive effect on the success of the new venture whereas founding and management experience have no effect. We discuss the implications of our findings from a perspective of entrepreneurship research as well as from a perspective of governmental start-up policy

Determinanten des Erfolgs staatlich geförderter Existenzgründungen – eine empirische Untersuchung

Ein Großteil der Neugründungen in Deutschland ist auf staatliche Förderung von Existenzgründern zurückzuführen. Dieser Anteil hat sich nach Einführung des als „Ich-AG“ bekannten Existenzgründungszuschusses Anfang 2003 stark erhöht. Die Erfolgsfaktorenforschung hat diese Form von Gründungen bislang jedoch wenig untersucht. Im Rahmen einer großzahligen Befragung von geförderten Existenzgründern untersucht dieser Beitrag die Erfolgsdeterminanten solcher geförderter Existenzgründungen. Die Ergebnisse der Analyse zeigen, dass der Gewinn aus der Existenzgründung bei älteren Gründern und bei Gründern mit einer langen Phase der Arbeitslosigkeit vor der Gründung seltener beziehungsweise erst später zur Bestreitung des Lebensunterhalts ausreicht. Dies gilt auch für Franchisegründungen und für Gründungen durch Frauen. In Bezug auf Bildungsvariablen, Gründungserfahrung und Teamgründungen im Vergleich zu Einzelgründungen wurde kein Effekt gefunden. Vorhandene Branchenerfahrung wirkt sich hingegen positiv auf den Erfolg der Gründung aus, Gründungs- und Führungserfahrung dagegen nicht. Die Implikationen unserer Ergebnisse für die Entrepreneurship-Forschung sowie für die Entrepreneurship-Praxis werden diskutiert. Herausforderungen aus Sicht der Gründungspolitik werden aufgezeigt.A large number of new ventures in Germany are undertaken due to government aid. With the introduction of the “Ich-AG” or “me-plc” in January 2003, this share has increased strongly. Entrepreneurship research so far has said very little about the success and the determinants of success of these types of start-ups. With this study, we aim to close this gap. We analyze the success and the determinants of success of these new ventures in a large scale survey of founders that have received governmental aid for their start-up. Our results show that the income generated by the venture is less likely to cover the costs of living in particular for elderly founders and for those founders that have experienced a long period of unemployment before they started their venture. This finding is also true for new ventures founded by women as well as for franchise start-ups. As concerns formal education, founder experience, and the fact whether the venture is founded by a team or not no significant effects exist. Industry experience, however, has a significant positive effect on the success of the new venture whereas founding and management experience have no effect. We discuss the implications of our findings from a perspective of entrepreneurship research as well as from a perspective of governmental start-up policy.Entrepreneurship; Self-employment; Necessity Entreptreneurship; Entrepreneurship Policy; Determinants of Success

Energy-Based switches losses model for the optimization of PwrSoC buck converter

Current trends in automotive industry impose as main drivers the improvement of the efficiency and the miniaturization of the electronic systems. New technologies for passives enable the integration of inductor based power converter together with the load in a single chip. Due to the complexity of the system and various constraints, multi-variable optimization needs to be employed. This study presents an energy-based piece-wise linear model for switches losses estimation for 40 nm automotive approved semiconductor technology used for implementation of PwrSoC buck converter system. The model, based on discrete number of calculations performed with Spice simulations, is presented in detail in this study and it is validated experimentally

Dynamics of Nanometer-Scale Foil Targets Irradiated with Relativistically Intense Laser Pulses

In this letter we report on an experimental study of high harmonic radiation generated in nanometer-scale foil targets irradiated under normal incidence. The experiments constitute the first unambiguous observation of odd-numbered relativistic harmonics generated by the $\vec{v}\times\vec{B}$ component of the Lorentz force verifying a long predicted property of solid target harmonics. Simultaneously the observed harmonic spectra allow in-situ extraction of the target density in an experimental scenario which is of utmost interest for applications such as ion acceleration by the radiation pressure of an ultraintense laser.Comment: 5 pages, 4 figure

Enhanced Proton Acceleration by an Ultrashort Laser Interaction with Structured Dynamic Plasma Targets

We experimentally demonstrate a notably enhanced acceleration of protons to high energy by relatively modest ultrashort laser pulses and structured dynamical plasma targets. Realized by special deposition of snow targets on sapphire substrates and using carefully planned pre-pulses, high proton yield emitted in a narrow solid angle with energy above 21MeV were detected from a 5TW laser. Our simulations predict that using the proposed scheme protons can be accelerated to energies above 150MeV by 100TW laser systems.Comment: Submitted to Physical Review Letter

Acquisition of pneumococci specific effector and regulatory Cd4+ T cells localising within human upper respiratory-tract mucosal lymphoid tissue

The upper respiratory tract mucosa is the location for commensal Streptococcus (S.) pneumoniae colonization and therefore represents a major site of contact between host and bacteria. The CD4(+) T cell response to pneumococcus is increasingly recognised as an important mediator of immunity that protects against invasive disease, with data suggesting a critical role for Th17 cells in mucosal clearance. By assessing CD4 T cell proliferative responses we demonstrate age-related sequestration of Th1 and Th17 CD4(+) T cells reactive to pneumococcal protein antigens within mucosal lymphoid tissue. CD25(hi) T cell depletion and utilisation of pneumococcal specific MHCII tetramers revealed the presence of antigen specific Tregs that utilised CTLA-4 and PDL-1 surface molecules to suppress these responses. The balance between mucosal effector and regulatory CD4(+) T cell immunity is likely to be critical to pneumococcal commensalism and the prevention of unwanted pathology associated with carriage. However, if dysregulated, such responses may render the host more susceptible to invasive pneumococcal infection and adversely affect the successful implementation of both polysaccharide-conjugate and novel protein-based pneumococcal vaccines

First Observation of Self-Amplified Spontaneous Emission in a Free-Electron Laser at 109 nm Wavelength

We present the first observation of Self-Amplified Spontaneous Emission (SASE) in a free-electron laser (FEL) in the Vacuum Ultraviolet regime at 109 nm wavelength (11 eV). The observed free-electron laser gain (approx. 3000) and the radiation characteristics, such as dependency on bunch charge, angular distribution, spectral width and intensity fluctuations all corroborate the existing models for SASE FELs.Comment: 6 pages including 6 figures; e-mail: [email protected]

Social capital of venture capitalists and start-up funding

How does the social capital of venture capitalists (VCs) affect the funding of start-ups? By building on the rich social capital literature, we hypothesize a positive effect of VCs' social capital, derived from past syndication, on the amount of money that start-ups receive. Specifically, we argue that both structural and relational aspects of VCs' social networks provide VCs with superior access to information about current investment objects and opportunities to leverage them in the future, increasing their willingness to invest in these firms. Our empirical results, derived from a novel dataset containing more than 1,500 first funding rounds in the Internet and IT sector, strongly confirm our hypotheses. We discuss the implications of our findings for theories of venture capital and entrepreneurship, showing that the role and effect of VCs' social capital on start-up firms may be more complex than previously argued in the literature