Strengthening Out-of-School Time Nonprofits: The Role of Foundations in Building Organizational Capacity

Placing nonprofits in the larger context of city, state, and national policy, explores the capacity-building support nonprofits running afterschool and summer programs need to provide high-impact networks of learning and developmental opportunities

Money, Real Interest Rates, and Output: A Reinterpretation of Postwar U.S. Data

This paper reexamines both monthly and quarterly U.S. postwar data to investigate if the observed comovements between money, real interestrates, prices and output are compatible with the money-real interest-output link suggested by existing monetary theories of output, which include both Keynesian and equilibrium models.The major empirical findings are these;1) In both monthly and quarterly data, we cannot reject the hypothesis that the ex ante real rate is exogenous, or Granger-causally prior in the context of a four-variable system which contains money, prices, nominal interest rates and industrial production.2) In quarterly data, there is significantly more information con-tained in either the levels of expected inflation or the innovationof this variable for predicting future output, given current and lagged output, than in any other variable examined (money, actualinflation, nominal interest rates, or ex ante real rates). The effect of an inflation innovation on future output is unambiguously negative. The first result casts strong doubt on the empirical importance of existing monetary theories of output, which imply that money should have a causal role on the ex ante real rates. The second result would appear incompatible with most demand driven models of output.In light of these results, we propose an alternative structural model which can account for the major dynamic interactions among the variables.This model has two central features: i) output is unaffected by money supply;and ii) the money supply process is motivated by short-run price stability.

Continuous-Time Random Walks at All Times

Continuous-time random walks (CTRW) play important role in understanding of a wide range of phenomena. However, most theoretical studies of these models concentrate only on stationary-state dynamics. We present a new theoretical approach, based on generalized master equations picture, that allowed us to obtain explicit expressions for Laplace transforms for all dynamic quantities for different CTRW models. This theoretical method leads to the effective description of CTRW at all times. Specific calculations are performed for homogeneous, periodic models and for CTRW with irreversible detachments. The approach to stationary states for CTRW is analyzed. Our results are also used to analyze generalized fluctuations theorem

The Exact Renormalization Group and Higher-spin Holography

In this paper, we revisit scalar field theories in $d$ space-time dimensions possessing $U(N)$ global symmetry. Following our recent work arXiv:1402.1430v2, we consider the generating function of correlation functions of all $U(N)$-invariant, single-trace operators at the free fixed point. The exact renormalization group equations are cast as Hamilton equations of radial evolution in a model space-time of one higher dimension, in this case $AdS_{d+1}$. The geometry associated with the RG equations is seen to emerge naturally out of the infinite jet bundle corresponding to the field theory, and suggests their interpretation as higher-spin equations of motion. While the higher-spin equations we obtain are remarkably simple, they are non-local in an essential way. Nevertheless, solving these bulk equations of motion in terms of a boundary source, we derive the on-shell action and demonstrate that it correctly encodes all of the correlation functions of the field theory, written as `Witten diagrams'. Since the model space-time has the isometries of the fixed point, it is possible to construct new higher spin theories defined in terms of geometric structures over other model space-times. We illustrate this by explicitly constructing the higher spin RG equations corresponding to the $z=2$ non-relativistic free field theory in $D$ spatial dimensions. In this case, the model space-time is the Schr\"odinger space-time, $Schr_{D+3}$.Comment: 37 pages, 3 figures; v2: Typos fixed, added discussion about boundary condition