Double parton scattering theory overview

The dynamics of double hard scattering in proton-proton collisions is quite involved compared with the familiar case of single hard scattering. In this contribution, we review our theoretical understanding of double hard scattering and of its interplay with other reaction mechanisms.Comment: 25 pages, 7 figures. Prepared for: Multiple Parton Interactions at the LHC, Eds. P. Bartalini and J. R. Gaunt, World Scientific, Singapor

The Auslander-Reiten Components in the Rhombic Picture

For an indecomposable module $M$ over a path algebra of a quiver of type $\widetilde{\mathbb A}_n$, the Gabriel-Roiter measure gives rise to four new numerical invariants; we call them the multiplicity, and the initial, periodic and final parts. We describe how these invariants for $M$ and for its dual specify the position of $M$ in the Auslander-Reiten quiver of the algebra.Comment: 29 pages; 6 figures; references added to Section 1 as per the referee's suggestions; to appear in Communications in Algebr

Assessment of Policy Instruments Toward a Sustainable Traffic System -A backcasting approach for Stockhom 2030

Finding strategies for preventing the process of global warming is growing urgent. Our intention is to highlight the future requirements and expectations on transport related sustainability measures (e.g. mobility management services, road tolls, CO2-taxes and renewable fuel systems) assisting the reaching of a long-term sustainability target of greenhouse gas emissions at the year 2030. We will employ the transport demand model SAMPERS and the traffic assignment model EMME/2 in order to investigate the effect from specific changes to the traffic network of Stockholm 2030, e.g. the environmental and socioeconomic impact from reduced number of commute trips, reduced car ownership, and new price structures and restrictions on private vehicle travel. In connection to this, we also quantify negative side effects (so-called rebound effects) coupled to efficiencies in the traffic network. We use an appraisal framework, influenced by backcasting, in order to assess the impact from the specific policies in relation to the United Nation’s (IPCC) requirements for a sustainable level of CO2-emissions. The findings from this study point at the inevitable need for at least a 50% renewable fuel mix in the traffic system if reaching the target 2030. Single-handedly, travel demand measures are insufficient to accomplish the CO2-emission target for 2030. Nevertheless, reducing traffic volumes by just a few percent might contribute to savings in emission costs, accident costs and aggregate travel time costs in the traffic system. Such measures are needed in order to mitigate the transition from fossil- to renewable fuels.

Optimized Unrestricted Kohn-Sham Potentials from Ab Initio Spin Densities

The reconstruction of the exchange-correlation potential from accurate ab initio electron densities can provide insights into the limitations of the currently available approximate functionals and provide guidance for devising improved approximations for density-functional theory (DFT). For open-shell systems, the spin density is introduced as an additional fundamental variable in Spin-DFT. Here, we consider the reconstruction of the corresponding unrestricted Kohn-Sham potentials from accurate ab initio spin densities. In particular, we investigate whether it is possible to reconstruct the spin exchange-correlation potential, which determines the spin density in spin-unrestricted Kohn-Sham-DFT, despite the numerical difficulties inherent to the optimization of potentials with finite orbital basis sets. We find that the recently developed scheme for unambiguously singling out an optimal optimized potential [J. Chem. Phys. 135, 244102 (2011)] can provide such spin potentials accurately. This is demonstrated for two test cases, the lithium atom and the dioxygen molecule, and target (spin) densities from Full-CI and CASSCF calculations, respectively

Statistical Matching of Administrative and Survey Data : An Application to Wealth Inequality Analysis

Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.Using population representative survey data from the German Socio-Economic Panel (SOEP) and administrative pension records from the Statutory Pension Insurance, the authors compare four statistical matching techniques to complement survey information on net worth with social security wealth (SSW) information from the administrative records. The unique properties of the linked data allow for a straight control of the quality of matches under each technique. Based on various evaluation criteria, Mahalanobis distance matching performs best. Exploiting the advantages of the newly assembled data, the authors include SSW in a wealth inequality analysis. Despite its quantitative relevance, SSW is thus far omitted from such analyses because adequate micro data are lacking. The inclusion of SSW doubles the level of net worth and decreases inequality by almost 25 percent. Moreover, the results reveal striking differences along occupational lines.Hans Böckler-Foundation, 2006-835-4, Erstellung und Analyse einer konsistenten Geld- und Realvermögensverteilungsrechnung für Personen und Haushalte 2002 und 2007 unter Berücksichtigung der personellen Einkommensverteilun

Item Non-response and Imputation of Annual Labor Income in Panel Surveys from a Cross-National Perspective

Using data on annual individual labor income from three representative panel datasets (German SOEP, British BHPS, Australian HILDA) we investigate a) the selectivity of item non-response (INR) and b) the impact of imputation as a prominent post-survey means to cope with this type of measurement error on prototypical analyses (earnings inequality, mobility and wage regressions) in a cross-national setting. Given the considerable variation of INR across surveys as well as the varying degree of selectivity build into the missing process, there is substantive and methodological interest in an improved harmonization of (income) data production as well as of imputation strategies across surveys. All three panels make use of longitudinal information in their respective imputation procedures, however, there are marked differences in the implementation. Firstly, although the probability of INR is quantitatively similar across countries, our empirical investigation identifies cross-country differences with respect to the factors driving INR: survey-related aspects as well as indicators accounting for variability and complexity of labor income composition appear to be relevant. Secondly, longitudinal analyses yield a positive correlation of INR on labor income data over time and provide evidence of INR being a predictor of subsequent unit-non-response, thus supporting the "cooperation continuum" hypothesis in all three panels. Thirdly, applying various mobility indicators there is a robust picture about earnings mobility being significantly understated using information from completely observed cases only. Finally, regression results for wage equations based on observed ("complete case analysis") vs. all cases and controlling for imputation status, indicate that individuals with imputed incomes, ceteris paribus, earn significantly above average in SOEP and HILDA, while this relationship is negative using BHPS data. However, once applying the very same imputation procedure used for HILDA and SOEP, namely the "row-and-columnimputation" approach suggested by Little & Su (1989), also to BHPS-data, this result is reversed, i.e., individuals in the BHPS whose income has been imputed earn above average as well. In our view, the reduction in crossnational variation resulting from sensitivity to the choice of imputation approaches underscores the importance of investing more in the improved cross-national harmonization of imputation techniques.Item non-response, imputation, income inequality, income mobility, panel data, SOEP, BHPS, HILDA

Old-Age Pension Entitlements Mitigate Inequality: But Concentration of Wealth Remains High

Entitlements from old-age pension schemes - statutory, company, and private - represent a considerable source of wealth. For data-related reasons, analyses of the personal wealth distribution have so far failed to take this into account, however. According to recent calculations based on the 2007 data of the German Socio- Economic Panel (SOEP), the present value of total pension and state annuity entitlements (not including entitlements to provision for dependants) amounted to roughly 4.6 trillion euros. This corresponds to an average of 67,000 euros per adult. When this is combined with individuals' financial and material assets, which amount to an average of 88,000 euros, the result is a more comprehensive total net worth of more than 155,000 euros. Civil servants and retired civil servants fare better than average if this larger view is taken. This more comprehensive measurement shows considerably less inequality of wealth than traditional analyses, which refer only to financial and material assets. This is not least because of the very widespread existence of entitlements under the various old-age pension schemes with simultaneous capping based on the contribution assessment threshold for statutory pension schemes. Nevertheless, wealth continues to be highly concentrated, and the mitigating effects of old-age pension assets will likely become less important in the future. Here the effects of falling pension levels as a result of reforms in the old-age pension systems and growing gaps in earnings histories will be felt - with the risk of increasing poverty among the future elderly.Wealth inequality, Pension entitlements, SOEP

Accounting for Imputed and Capital Income Flows in Income Inequality Analyses

Using representative and consistent microdata from the German Socio-Economic Panel Study (SOEP) from 1985-2007, we illustrate that capital income (CI = return on financial investments) and imputed rent (IR = return on investments in owner-occupied housing) have become increasingly important sources of economic inequality in Germany over the last two decades. Whereas the operationalization of CI in this paper is based on monetary returns on financial investments only, our definition of IR follows a regulation by the European Commission, (EC) which is currently being used to harmonize income measurement for the European Statistics on Income and Living Conditions (EU-SILC) in Europe. While both of these components represent some kind of return on alternative private investments, our results indicate that they do not coincide in their impacts on income inequality and poverty. In line with the literature, net IR as defined according to the EC regulation tends to exert a dampening effect on inequality and relative poverty, very much driven by the increasing share of outright ownership among the elderly. On the other hand, inequality is boosted by CI especially when looking at the upper tail of the income distribution. As the German public pension scheme gradually loses its ability to maintain people's living standards into retirement, we find these effects to increase over time. The analyses presented here, exemplified for Germany, make a clear case for the joint consideration of all components of private investment income for the purpose of welfare analysis, be they of a monetary or non-monetary nature. This appears to be relevant in at least three dimensions of comparative research: (1) across time; (2) across space, regions, welfare regimes; (3) across the individual life course, thus analyzing the impact of investment income on intrapersonal mobility patterns.income inequality, decomposition, capital income, imputed rent, SOEP

Community based trial of home blood pressure monitoring with nurse-led telephone support in patients with stroke or transient ischaemic attack recently discharged from hospital.

BACKGROUND: High blood pressure in patients with stroke increases the risk of recurrence but management in the community is often inadequate. Home blood pressure monitoring may increase patients' involvement in their care, increase compliance, and reduce the need for patients to attend their General Practitioner if blood pressure is adequately controlled. However the value of home monitoring to improve blood pressure control is unclear. In particular its use has not been evaluated in stroke patients in whom neurological and cognitive ability may present unique challenges. DESIGN: Community based randomised trial with follow up after 12 months. PARTICIPANTS: 360 patients admitted to three South London Stroke units with stroke or transient ischaemic attack within the past 9 months will be recruited from the wards or outpatients and randomly allocated into two groups. All patients will be visited by the specialist nurse at home at baseline when she will measure their blood pressure and administer a questionnaire. These procedures will be repeated at 12 months follow up by another researcher blind as to whether the patient is in intervention or control group. INTERVENTION: INTERVENTION patients will be given a validated home blood pressure monitor and support from the specialist nurse. Control patients will continue with usual care (blood pressure monitoring by their practice). Main outcome measures in both groups after 12 months: 1. Change in systolic blood pressure.2. Cost effectiveness: Incremental cost of the intervention to the National Health Service and incremental cost per quality adjusted life year gained