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Learn the ins and outs of equity crowdfunding with this informative guide Equity Crowdfunding for Investors is a comprehensive, objective, and authoritative guide to the social and financial rewards of crowdfunding. Before now, angel investing - and the spectacular returns possible in this asset class - has been off-limits to all but the wealthiest Americans. Now equity crowdfunding portals allow the general public to buy shares in startups and fast-growing private companies for the first time in generations. This book provides the guidance individuals need to invest wisely, tempering the exc

Angesichts der hohen Arbeitslosigkeit wurden in verschiedenen Ländern spezielle Maßnahmen zur Bekämpfung der Arbeitslosigkeit ergriffen (Zeitarbeit, Weiterbildung; Förderung von Unternehmensgründungen durch Arbeitslose). In dem Artikel werden Maßnahmen in sieben OECD-Länder beschrieben; auf Inhalte, Struktur, Implementation und Finanzierung eingegangen. Schwachpunkte werden ebenfalls aufgez eigt und die Notwendigkeit von Wirkungsanalysen betont. (IAB)

The Collegiate Learning Assessment (CLA) program measures value added in colleges and universities, by testing the ability of freshmen and seniors to think logically and write clearly. The program is popular enough that it has attracted critics. In this paper, we outline the methods used by the CLA to determine value added. We summarize the criticisms, which revolve around the question of which students take the CLA tests. Typically, samples are not random, so that selection bias is a concern, as is confounding. We respond by showing that criticisms of CLA procedures are not supported by the data.

Crouch and Wilson demonstrated a strong correlation between carcinogenic potencies in rats and mice, supporting the extrapolation from mouse to man. Bernstein et al., however, show that the observed correlation is mainly a statistical artifact of bioassay design. Crouch et al. have a comeback. This paper will review the arguments and present some new data. The correlation is largely (but not totally) tautological, confirming results in Bernstein et al.

Ecological regression is a statistical mainstay in litigation brought under the Voting Rights Act of 1965. The technique is discussed in the context of a suit against the County of Los Angeles that came to trial in 1990. Ecological regression depends on very strong assumptions about political behavior The authors identify these assumptions and show that they are not supported by the data. Also described is an alternative "neighborhood model, " which is a priori more plausible and fits the facts better. The neighborhood model leads to quite different conclusions about voting behavior.

Considering the difficulties, the Census Bureau does a remarkably good job at counting people. This article discusses techniques for adjusting the census. If there is a large undercount, these techniques may be accurate enough for adjustment. With a small undercount, adjustment could easily degrade the accuracy of the data. The Bureau argued that errors in the census were more serious than errors in the proposed adjustment, using "loss function analysis" to balance the risks. This procedure turns out to depend on quite unreasonable assumptions. With other and more realistic assumptions, the balance favors the census. The story has a broader moral. Statistical models are often defended on grounds of robustness. However, internally generated measures of precision may be critical. If the model is at all complicated, these measures of precision may turn out to be driven by assumptions not data—the antithesis of robustness.

Considering the difficulties, the Census Bureau does a remarkably good job at counting people. This article discusses techniques for adjusting the census. If there is a large undercount, these techniques may be accurate enough for adjustment. With a small undercount, they are unlikely to improve on the census; instead, adjustment could easily degrade the accuracy of the data. The focus will be sampling error, that is, uncertainty in estimates due to the luck of the draw in choosing the sample. Sampling error is a major obstacle to adjusting the 1990 census, even at the state level. To control sampling error, the Census Bureau used a smoothing model. However, the model does not solve the problem, because its effects are strongly dependent on unverified and implausible assumptions. This story has a broader moral. Statistical models are often defended on grounds of robustness, that is, estimates do not depend strongly on assumptions. But the standard errors, which are internally generated measures of precision, may be critical. Then caution is in order. If the model is at all complicated, the standard errors may turn out to be driven by assumptions not data—the antithesis of robustness.

This study investigates, for the first time, dual C-Cl isotope fractionation during anaerobic biodegradation of 1,2-dichloroethane (1,2-DCA) via dihaloelimination by Dehalococcoides and Dehalogenimonas-containing enrichment cultures. Isotopic fractionation of 1,2-DCA (εbulkC and εbulkCl) for Dehalococcoides (-33.0 ± 0.4‰ and -5.1 ± 0.1‰) and Dehalogenimonas-containing microcosms (-23 ± 2‰ and -12.0 ± 0.8‰) resulted in distinctly different dual element C-Cl isotope correlations (∇ = Δδ13C/Δδ37Cl ≈ εbulkC/εbulkCl), 6.8 ± 0.2 and 1.89 ± 0.02, respectively. Determined isotope effects and detected products suggest that the difference on the obtained ∇ values for biodihaloelimination could be associated with a different mode of concerted bond cleavage rather than two different reaction pathways (i.e., stepwise vs concerted). ∇ values of 1,2-DCA were, for the first time, determined in two field sites under reducing conditions (2.1 ± 0.1 and 2.2 ± 2.9). They were similar to the one obtained for the Dehalogenimonas-containing microcosms (1.89 ± 0.02) and very different from those reported for aerobic degradation pathways in a previous laboratory study (7.6 ± 0.1 and 0.78 ± 0.03). Thus, this study illustrates the potential of a dual isotope analysis to differentiate between aerobic and anaerobic biodegradation pathways of 1,2-DCA in the field and suggests that this approach might also be used to characterize dihaloelimination of 1,2-DCA by different bacteria, which needs to be confirmed in future studies. © 2017 American Chemical Society. ; We thoroughly thank four anonymous reviewers for their helpful comments on the manuscript. J.P. was supported by the University of Neuchatel via direct university funding. E.M-U is ̂ supported by the Spanish Ministry of Economy and Competitiveness and FEDER (project CTM2013-48545-C2- 1-R) and the Xarxa de Referencia en Biotecnologia de la ̀ Generalitat de Catalunya. MAG group is supported by Spanish Government REMEDIATION project (CGL2014-57215-C4-1- R) and the Catalan Government project 2014SGR-1456. S.H.M acknowledges support from the Ministry of Education Malaysia (SLAI-UMP Scholarship) for a predoctoral fellowship and M.R. a Ramon y Cajal contract (RYC-2012-11920). ; Peer reviewed