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Entrepreneurial workaround practices in severe institutional voids: Evidence from Kenya
Entrepreneurs in developing economies try to cope with weak or absent formal institutions â often referred to as âinstitutional voidsâ â by relying extensively on intermediary organizations such as business incubators and development organizations or informal institutions such as political, kinship, or family relationships. However, in many African countries, intermediary support is limited and informal institutions are also unreliable, adding risks and costs to doing business and increasing the severity of institutional voids in the surrounding ecosystem. We investigate the practices followed by 47 commercial entrepreneurs in Kenya to âwork aroundâ these severe institutional voids to achieve their goals of business creation and growth. We find that severe institutional voids stimulate the hybridization of goals to include social value creation, create a need for a more strategic orchestration of business relationships, and motivate entrepreneurs to proactively cross-brace the institutional infrastructure around them. We contribute by unveiling the important role of entrepreneurs as microinstitutional agents in developing economies and by detailing how commercial and social goals become intertwined in the context of African entrepreneurship
On the ignorance of group-level effects â The tragedy of personnel evaluation?
In social-dilemma situations (e.g., public-good games), people may pursue their local self- interests, thereby lowering the overall payoff of their group and, paradoxically, even their individual payoffs as a result. Likewise, in inner-individual dilemmas, even without conflict of interest between persons, people may pursue local goals at the expense of overall utility. Our experiments investigate such dissociations of individual and group-level effects in the context of personnel evaluation and selection. Participants were given the role of human resource managers selecting workers to optimize the overall payoff for the company. We investigated contexts where the individually best/worst âemployeesâ systematically caused the worst/best group performance. When workers in a team could substantially increase or decrease co-workersâ performance, most participants (albeit not all) tended to focus solely on individual performance without considering their overall contribution even when instructed to maximize group performance. This undue focus on individual information meant that employees who enhanced team performance the most often received the most negative evaluations. This may result in a âtragedy of personnel evaluationâ relevant to maladaptive incentive structures (personnel evaluation), job offers (personnel selection), and a substantially negative impact on organizational effectiveness. At the same time, the results suggest ways this problem may be overcome
Formal models of source reliability
The paper introduces, compares and contrasts formal models of source reliability proposed in the epistemology literature, in particular the prominent models of Bovens and Hartmann (2003) and Olsson (2011). All are Bayesian models seeking to provide normative guidance, yet they differ subtly in assumptions and resulting behavior. Models are evaluated both on conceptual grounds and through simulations, and the relationship between models is clarified. The simulations both show surprising similarities and highlight relevant differences between these models. Most importantly, however, our evaluations reveal that important normative concerns arguably remain unresolved. The philosophical implications of this for testimony are discussed
Nanocomposites based on poly(glycerol sebacate) with silica nanoparticles with potential application in dental tissue engineering
"This is an Accepted Manuscript of an article published by Taylor & Francis inInternational Journal of Polymeric Materials and Polymeric Biomaterials on AUG 08 2020, available online: https://www.tandfonline.com/doi/full/10.1080/00914037.2019.1616197"[EN] Nanocomposites based on poly(glycerol sebacate) with silica nanoparticles were synthesized to explore their potential use in the biomedical field. The nanoparticles were two distinct polyhedral oligomeric silsesquioxanes (POSS), both used at 5% wt/wt concentration, specifically methacrylisobutyl POSS and methacryl POSS. These materials were investigated for their possible application as coatings as well as with regenerative purposes in dental engineering, and their viability for this application was assessed. Thus, pure PGS and nanohybrids thereof were obtained as scaffolds (that is, porous structures, designed with regenerative purposes) and as films (intended for coatings and to be used as controls).The authors acknowledge Dr. Kirsten Techmer from Geoscience Center of the Georg-August-University Gottingen for performing the EDX-SEM analysis, the assistance and advice of the Julich Center for Neutron Science (JCNS) and Institute for Complex Systems (ICS), Forschungszentrum Julich GmbH (Germany), and the Electron Microscopy Service of the Universitat Politecnica de Valencia (Spain). This work was partially funded by the Spanish Ministerio de EconomĂa y Competitividad through DPI2015-65401-C3-2-R project and by the German Research Foundation [DFG/MWK INST 1525/39-1 FUGG]. A.V.-Ll. acknowledges the support of the Generalitat Valenciana, Conselleria de EducaciĂłn, InvestigaciĂłn, Cultura y Deporte through project AEST/2018/014.TallĂĄ Ferrer, C.; Vilariño, G.; Rizk, M.; Sydow, H.; VallĂ©s Lluch, A. (2020). Nanocomposites based on poly(glycerol sebacate) with silica nanoparticles with potential application in dental tissue engineering. International Journal of Polymeric Materials. 69(12):761-772. https://doi.org/10.1080/00914037.2019.1616197S7617726912Wang, Y., Ameer, G. A., Sheppard, B. J., & Langer, R. (2002). A tough biodegradable elastomer. Nature Biotechnology, 20(6), 602-606. doi:10.1038/nbt0602-602Loh, X. J., Abdul Karim, A., & Owh, C. (2015). Poly(glycerol sebacate) biomaterial: synthesis and biomedical applications. Journal of Materials Chemistry B, 3(39), 7641-7652. doi:10.1039/c5tb01048aRai, R., Tallawi, M., Grigore, A., & Boccaccini, A. R. (2012). Synthesis, properties and biomedical applications of poly(glycerol sebacate) (PGS): A review. Progress in Polymer Science, 37(8), 1051-1078. doi:10.1016/j.progpolymsci.2012.02.001Serrano, M. C., Chung, E. J., & Ameer, G. A. (2010). Advances and Applications of Biodegradable Elastomers in Regenerative Medicine. Advanced Functional Materials, 20(2), 192-208. doi:10.1002/adfm.200901040Zhang, X., Jia, C., Qiao, X., Liu, T., & Sun, K. (2016). Porous poly(glycerol sebacate) (PGS) elastomer scaffolds for skin tissue engineering. Polymer Testing, 54, 118-125. doi:10.1016/j.polymertesting.2016.07.006MacDonald, R. A., Laurenzi, B. F., Viswanathan, G., Ajayan, P. M., & Stegemann, J. P. (2005). Collagen-carbon nanotube composite materials as scaffolds in tissue engineering. Journal of Biomedical Materials Research Part A, 74A(3), 489-496. doi:10.1002/jbm.a.30386Saito, N., Usui, Y., Aoki, K., Narita, N., Shimizu, M., Hara, K., ⊠Endo, M. (2009). Carbon nanotubes: biomaterial applications. Chemical Society Reviews, 38(7), 1897. doi:10.1039/b804822nChawla, R., Tan, A., Ahmed, M., Crowley, C., Moiemen, N. S., Cui, Z., ⊠Seifalian, A. M. (2014). A polyhedral oligomeric silsesquioxaneâbased bilayered dermal scaffold seeded with adipose tissueâderived stem cells: in vitro assessment of biomechanical properties. Journal of Surgical Research, 188(2), 361-372. doi:10.1016/j.jss.2014.01.006Campbell, K., Craig, D. Q. M., & McNally, T. (2008). Poly(ethylene glycol) layered silicate nanocomposites for retarded drug release prepared by hot-melt extrusion. International Journal of Pharmaceutics, 363(1-2), 126-131. doi:10.1016/j.ijpharm.2008.06.027Scott, D. W. (1946). Thermal Rearrangement of Branched-Chain Methylpolysiloxanes1. Journal of the American Chemical Society, 68(3), 356-358. doi:10.1021/ja01207a003Conejero-GarcĂa, Ă., Gimeno, H. R., SĂĄez, Y. M., Vilariño-Feltrer, G., Ortuño-LizarĂĄn, I., & VallĂ©s-Lluch, A. (2017). Correlating synthesis parameters with physicochemical properties of poly(glycerol sebacate). European Polymer Journal, 87, 406-419. doi:10.1016/j.eurpolymj.2017.01.001Gao, J., Crapo, P. M., & Wang, Y. (2006). Macroporous Elastomeric Scaffolds with Extensive Micropores for Soft Tissue Engineering. Tissue Engineering, 12(4), 917-925. doi:10.1089/ten.2006.12.917Klimek, J., Hellwig, E., & Ahrens, G. (1982). Fluoride Taken Up by Plaque, by the Underlying Enamel and by Clean Enamel from Three Fluoride Compounds in vitro. Caries Research, 16(2), 156-161. doi:10.1159/000260592Zhao, X., Wu, Y., Du, Y., Chen, X., Lei, B., Xue, Y., & Ma, P. X. (2015). A highly bioactive and biodegradable poly(glycerol sebacate)âsilica glass hybrid elastomer with tailored mechanical properties for bone tissue regeneration. Journal of Materials Chemistry B, 3(16), 3222-3233. doi:10.1039/c4tb01693aWu, Y., Shi, R., Chen, D., Zhang, L., & Tian, W. (2011). Nanosilica filled poly(glycerol-sebacate-citrate) elastomers with improved mechanical properties, adjustable degradability, and better biocompatibility. Journal of Applied Polymer Science, 123(3), 1612-1620. doi:10.1002/app.34556Liang, S.-L., Cook, W. D., Thouas, G. A., & Chen, Q.-Z. (2010). The mechanical characteristics and in vitro biocompatibility of poly(glycerol sebacate)-BioglassÂź elastomeric composites. Biomaterials, 31(33), 8516-8529. doi:10.1016/j.biomaterials.2010.07.105Kokubo, T., & Takadama, H. (2006). How useful is SBF in predicting in vivo bone bioactivity? Biomaterials, 27(15), 2907-2915. doi:10.1016/j.biomaterials.2006.01.017Wahab, M. A., Kim, I., & Ha, C.-S. (2003). Microstructure and properties of polyimide/poly(vinylsilsesquioxane) hybrid composite films. Polymer, 44(16), 4705-4713. doi:10.1016/s0032-3861(03)00429-4Yan Song, X., Ping Geng, H., & Li, Q. F. (2006). The synthesis and characterization of polystyrene/magnetic polyhedral oligomeric silsesquioxane (POSS) nanocomposites. Polymer, 47(9), 3049-3056. doi:10.1016/j.polymer.2006.02.055Kerativitayanan, P., & Gaharwar, A. K. (2015). Elastomeric and mechanically stiff nanocomposites from poly(glycerol sebacate) and bioactive nanosilicates. Acta Biomaterialia, 26, 34-44. doi:10.1016/j.actbio.2015.08.025Liu, J., Zheng, H., Poh, P., Machens, H.-G., & Schilling, A. (2015). Hydrogels for Engineering of Perfusable Vascular Networks. International Journal of Molecular Sciences, 16(7), 15997-16016. doi:10.3390/ijms160715997Gibson, L. J., & Ashby, M. F. (1997). Cellular Solids. doi:10.1017/cbo9781139878326VallĂ©s Lluch, A., Gallego Ferrer, G., & MonleĂłn Pradas, M. (2009). Biomimetic apatite coating on P(EMA-co-HEA)/SiO2 hybrid nanocomposites. Polymer, 50(13), 2874-2884. doi:10.1016/j.polymer.2009.04.022Jones, J. R. (2006). Scaffolds for Cell and Tissue Engineering. Wiley Encyclopedia of Biomedical Engineering. doi:10.1002/9780471740360.ebs140
Networking to death: on the dark side of start-upsâ external networking
Purpose
Many start-ups do not survive the first few years of business. Previous studies suggest that networks play a role in start-ups' success, but this positive effect has limits. The purpose of this paper is to answer the call for a better understanding of the dark side of networks and the variables that condition variables' effect on the likelihood of start-ups' survival.
Design/methodology/approach
A longitudinal research design includes 139 start-ups (102 from Germany and 37 from Portugal) and a total of 252 participants. A generalized linear mixed model (GLMM)was applied to estimate all the coefficients, to test the mediation (H1), the moderation (H2) and the moderated mediation (H3) while considering the economic situation of the start-up (sales growth), start-ups' networking behavior, creativity orientation and ultimately the likelihood of survival.
Findings
Based on an empirical study from two different countries, the results show that effective networking is contingent on the start-up's economic situation and creative potential. Specifically, the results point to situations in which early sales growth may lead to external networking, which, in contexts of low creativity-oriented start-ups, can compromise the start-ups' success.
Originality/value
Based on the findings, the authors compare scenarios in which networking increases the chances for start-up survival with situations where networking can have adverse effects. This study highlights the importance of considering specific start-up parameters, such as start-ups' economic situation and level of creativity orientation, in the business venturing literature
Networking to death: On the dark side of start-upsâ external networking
Purpose â Many start-ups do not survive the first few years of business. Previous studies suggest that
networks play a role in start-upsâ success, but this positive effect has limits. The purpose of this paper is to
answer the call for a better understanding of the dark side of networks and the variables that condition
variablesâ effect on the likelihood of start-upsâ survival.
Design/methodology/approach âAlongitudinal research design includes 139 start-ups (102 from Germany
and 37 from Portugal) and a total of 252 participants. A generalized linear mixed model (GLMM)was applied to
estimate all the coefficients, to test the mediation (H1), the moderation (H2) and the moderated mediation (H3)
while considering the economic situation of the start-up (sales growth), start-upsâ networking behavior,
creativity orientation and ultimately the likelihood of survival.
Findings â Based on an empirical study from two different countries, the results show that effective
networking is contingent on the start-upâs economic situation and creative potential. Specifically, the results
point to situations in which early sales growth may lead to external networking, which, in contexts of low
creativity-oriented start-ups, can compromise the start-upsâ success.
Originality/value â Based on the findings, the authors compare scenarios in which networking increases the
chances for start-up survival with situations where networking can have adverse effects. This study highlights
the importance of considering specific start-up parameters, such as start-upsâ economic situation and level of
creativity orientation, in the business venturing literature.info:eu-repo/semantics/publishedVersio
How good is your evidence and how would you know?
This paper examines the basic question of how we can come to form accurate beliefs about the world when we do not fully know how good or bad our evidence is. Here we show, using simulations with otherwise optimal agents, the cost of misjudging the quality of our evidence, and compare different strategies for correctly estimating that quality, such as outcome, and expectation-based updating. We identify conditions under which misjudgment of evidence quality can nevertheless lead to accurate beliefs, as well as those conditions where no strategy will help. These results indicate both where people will nevertheless succeed and where they will fail when information quality is degraded
Knowledge through social networks: accuracy, error, and polarisation
This paper examines the fundamental problem of testimony. Much of what we believe to know we know in good part, or even entirely, through the testimony of others. The problem with testimony is that we often have very little on which to base estimates of the accuracy of our sources. Simulations with otherwise optimal agents examine the impact of this for the accuracy of our beliefs about the world. It is demonstrated both where social networks of information dissemination help and where they hinder. Most importantly, it is shown that both social networks and a common strategy for gauging the accuracy of our sources give rise to polarisation even for entirely accuracy motivated agents. Crucially these two factors interact, amplifying one anotherâs negative consequences, and this side effect of communication in a social network increases with network size. This suggests a new causal mechanism by which social media may have fostered the increase in polarisation currently observed in many parts of the world
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