The One-Loop Matter Bispectrum in the Effective Field Theory of Large Scale Structures

Given the importance of future large scale structure surveys for delivering new cosmological information, it is crucial to reliably predict their observables. The Effective Field Theory of Large Scale Structures (EFTofLSS) provides a manifestly convergent perturbative scheme to compute the clustering of dark matter in the weakly nonlinear regime in an expansion in $k/k_{\rm NL}$, where $k$ is the wavenumber of interest and $k_{\rm NL}$ is the wavenumber associated to the nonlinear scale. It has been recently shown that the EFTofLSS matches to $1\%$ level the dark matter power spectrum at redshift zero up to $k\simeq 0.3 h\,$Mpc$^{-1}$ and $k\simeq 0.6 h\,$Mpc$^{-1}$ at one and two loops respectively, using only one counterterm that is fit to data. Similar results have been obtained for the momentum power spectrum at one loop. This is a remarkable improvement with respect to former analytical techniques. Here we study the prediction for the equal-time dark matter bispectrum at one loop. We find that at this order it is sufficient to consider the same counterterm that was measured in the power spectrum. Without any remaining free parameter, and in a cosmology for which $k_{\rm NL}$ is smaller than in the previously considered cases ($\sigma_8=0.9$), we find that the prediction from the EFTofLSS agrees very well with $N$-body simulations up to $k\simeq 0.25 h\,$Mpc$^{-1}$, given the accuracy of the measurements, which is of order a few percent at the highest $k$'s of interest. While the fit is very good on average up to $k\simeq 0.25 h\,$Mpc$^{-1}$, the fit performs slightly worse on equilateral configurations, in agreement with expectations that for a given maximum $k$, equilateral triangles are the most nonlinear.Comment: 39 pages, 12 figures; v2: JCAP published version, improved numerical data, added explanation and clarification

When is capital enough to get female microenterprises growing? Evidence from a randomized experiment in Ghana

Standard models of investment predict that credit-constrained firmd should grow rapidly when given additional capital, and that how this capital is provided should not affect decisions to invest in the business or consume the capital. We randomly gave cash and in-kind grants to male- and female- owned microenterprises in urban Ghana. Our findings cast doubt on the ability of caoital alone to stimulate the growth of female microenterprises. First, while the average treatment effects of the in-kind grants are large and positive for both males and females, the gain in profits is almost zerp fpr women with itital profits below the median, suggesting that capital alone is not enough to grow subsistence enterprises owned by women. Second, for women we strongly reject equality of the case and in-kind grants; only in-kind grants lead to growth in business profits. The results for men also suggest a lower impact of cash, but differences between cash and in-kind grants is assoicated more with a lack of self-control than with external pressure. As a result, the manner in which funding is provided affects microenterprise growth.microenterprises; ghana; Conditionality; Asset intergration

The effects of halo alignment and shape on the clustering of galaxies

We investigate the effects of halo shape and its alignment with larger scale structure on the galaxy correlation function. We base our analysis on the galaxy formation models of Guo et al., run on the Millennium Simulations. We quantify the importance of these effects by randomizing the angular positions of satellite galaxies within haloes, either coherently or individually, while keeping the distance to their respective central galaxies fixed. We find that the effect of disrupting the alignment with larger scale structure is a ~2 per cent decrease in the galaxy correlation function around r=1.8 Mpc/h. We find that sphericalizing the ellipsoidal distributions of galaxies within haloes decreases the correlation function by up to 20 per cent for r<1 Mpc/h and increases it slightly at somewhat larger radii. Similar results apply to power spectra and redshift-space correlation functions. Models based on the Halo Occupation Distribution, which place galaxies spherically within haloes according to a mean radial profile, will therefore significantly underestimate the clustering on sub-Mpc scales. In addition, we find that halo assembly bias, in particular the dependence of clustering on halo shape, propagates to the clustering of galaxies. We predict that this aspect of assembly bias should be observable through the use of extensive group catalogues.Comment: 8 pages, 6 figures. Accepted for publication in MNRAS. Minor changes relative to v1. Note: this is an revised and considerably extended resubmission of http://arxiv.org/abs/1110.4888; please refer to the current version rather than the old on

Integration von Flüchtlingen: Eine langfristig lohnende Investition

Der starke Zustrom von Flüchtlingen heizt die Diskussionen in Deutschland an. Dabei wird oft nur auf kurzfristige Kosten geschaut, die in den kommenden Jahren zweifellos massiv sein werden. Dies versperrt den Blick auf potentielle Chancen, die die Zuwanderung - oftmals junger Menschen - der deutschen Gesellschaft bietet. Gelingt die Integration in den Arbeitsmarkt, werden die anfänglichen Ausgaben zu einer Investition in die Zukunft: Selbst wenn viele Flüchtlinge aufgrund fehlender Qualifikationen kurzfristig vergleichsweise schlechte Aussichten am Arbeitsmarkt haben und diejenigen, die den Weg in eine Beschäftigung finden, oftmals unterdurchschnittlich produktiv sind, werden langfristig die positiven wirtschaftlichen Impulse für Deutschland die Kosten übertreffen. Wenngleich offenkundig noch detailliertere Studien erforderlich sind, um die Effekte genauer einzugrenzen, versucht dieser Bericht, anhand einfacher Simulationsrechnungen das Potential einer Integration zu umreißen, das auf lange Sicht betrachtet die anfänglichen Kosten durchaus rechtfertigt. Dabei werden neben einem Basisszenario ein optimistisches undein pessimistisches Szenario untersucht. Es kann nicht stark genug betont werden, dass es sich hierbei um Simulationen handelt und nicht um Prognosen, die versuchen, die Zukunft vorherzusagen. Die zentrale Frage ist nicht, ob die Flüchtlinge langfristig einen wirtschaftlichen Nutzen für Deutschland bedeuten, sondern lediglich, wie schnell die Leistungen der Flüchtlinge die zusätzlichen Ausgaben übertreffen. Denn auch wenn die Integration in den Arbeitsmarkt langsamer verlaufen sollte als erhofft, so werden die Flüchtlinge langfristig einen positiven wirtschaftlichen Beitrag für Deutschland leisten. Mehr noch: Auch die bereits in Deutschland lebenden Bürger werden langfristig von der Zuwanderung profitieren und ein höheres Pro-Kopf-Einkommen erzielen.The debate about the massive influx of refugees into Germany often focuses solely on the short-term costs. But while these expenditures are bound to be substantial in the coming years, the discussion neglects the long-term economic potential of a successful integration of refugees-often, young people-which can transform the initial expenditure into a worthwhile investment. Even if many of the refugees' labor market prospects may be relatively poor for the first few years due to a lack of qualifications, and those who do find employment may be less productive than the average German worker, the long-term gains are likely to exceed the costs. This study uses simple simulated calculations to outline the economic potential by comparing the costs and benefits of an integration in the long run. In addition to a baseline scenario, this article investigates both an optimistic and a pessimistic scenario. (It should be emphasized, however, that these are simulations and not forecasts-clearly, more detailed studies are needed to measure these effects more precisely.) The central question boils down to when, not whether, the integration of refugees gains sufficient momentum to outweigh the costs-because even if the labor market integration turns out to be sluggish, the refugees will still have a positive impact on the German economy after five to ten years. Most importantly, even in terms of per capita income of non-refugees, the benefits will exceed the costs in the long-term, thus highlighting the benefits to the entire economy

Convolutional Patch Networks with Spatial Prior for Road Detection and Urban Scene Understanding

Classifying single image patches is important in many different applications, such as road detection or scene understanding. In this paper, we present convolutional patch networks, which are convolutional networks learned to distinguish different image patches and which can be used for pixel-wise labeling. We also show how to incorporate spatial information of the patch as an input to the network, which allows for learning spatial priors for certain categories jointly with an appearance model. In particular, we focus on road detection and urban scene understanding, two application areas where we are able to achieve state-of-the-art results on the KITTI as well as on the LabelMeFacade dataset. Furthermore, our paper offers a guideline for people working in the area and desperately wandering through all the painstaking details that render training CNs on image patches extremely difficult.Comment: VISAPP 2015 pape

The Dutch Energy Markets in 2009: Target Scenario – Obstacles – Measures

Competition on the wholesale gas market is still in its early stages. Measures have already been put in place to eliminate some shortcomings, these are the new market model and the market-based balancing system. Both of these are the result of the Gas Letter from the Minister and the underlying TTF advice from the NMa. These measures facilitate a development towards more competition. But for a better functioning market the commitment of all market participants is required. Gasterra, the exclusive marketer of Groningen gas, has a key responsibility here. Energy suppliers should be able to obtain gas on the TTF in the required periods and quantities. Otherwise the development of the wholesale gas market will just be stalled further.Monitoring, electricity, gas, competition, infrastructure