11,436 research outputs found
Economic policy uncertainty and small business expansion
Is uncertainty causing small business owners to behave in ways that are hindering the recovery? That question is at the center of an intense public debate. Though reasonable arguments have been presented on both sides, there is not much empirical evidence to draw on. To contribute some to the discussion, we investigated the statistical association between data on small business plans to hire and make capital expenditures and a measure of policy uncertainty. Our analysis suggests that uncertainty is adversely affecting small business owners’ expansion plans.Small business ; Economic conditions - United States
State growth empirics: the long-run determinants of state income growth
Real average U.S. per capita personal income growth over the last 65 years exceeded a remarkable 400 percent. Also notable over this period is that the stark income differences across states have narrowed considerably: In 1939 the highest income state’s per capita personal income was 4.5 times the lowest, but by 1976 this ratio had fallen to less than 2 times. Since 1976, the standard deviation of per capita incomes at the state level has actually risen, as some higher-income states have seen their income levels rise relative to the median of the states. A better understanding of the sources of these relative growth performances should help to characterize more effective economic development strategies, if income growth differences are predictable. In this paper, we look for statistically and economically significant growth factors by estimating an augmented growth model using a panel of the 48 contiguous states from 1939 to 2004. Specifically, we control for factors that previous researchers have argued were important: tax burdens, public infrastructure, size of private financial markets, rates of business failure, industry structure, climate, and knowledge stocks. Our results, which are robust to a wide variety of perturbations to the model, are easily summarized: A state’s knowledge stocks (as measured by its stock of patents and its high school and college attainment rates) are the main factors explaining a state’s relative per capita personal income.Economic development ; Income ; Education - Economic aspects
Experimental validation of phase space conduits of transition between potential wells
A phase space boundary between transition and non-transition, similar to
those observed in chemical reaction dynamics, is shown experimentally in a
macroscopic system. We present a validation of the phase space flux across rank
one saddles connecting adjacent potential wells and confirm the underlying
phase space conduits that mediate the transition. Experimental regions of
transition are found to agree with the theory to within 1\%, suggesting the
robustness of phase space conduits of transition in a broad array of two or
more degree of freedom experimental systems, despite the presence of small
dissipation.Comment: 7 pages, 6 figure
Heteroclinic connections between periodic orbits and resonance transitions in celestial mechanics
In this paper we apply dynamical systems techniques to the problem of heteroclinic connections and resonance transitions in the planar circular restricted three-body problem. These related phenomena have been of concern for some time in topics such as the capture of comets and asteroids and with the design of trajectories for space missions such as the Genesis Discovery Mission. The main new technical result in this paper is the numerical demonstration of the existence of a heteroclinic connection between pairs of periodic orbits: one around the libration point L1 and the other around L2, with the two periodic orbits having the same energy. This result is applied to the resonance transition problem and to the explicit numerical construction of interesting orbits with prescribed itineraries. The point of view developed in this paper is that the invariant manifold structures associated to L1 and L2 as well as the aforementioned heteroclinic connection are fundamental tools that can aid in understanding dynamical channels throughout the solar system as well as transport between the "interior" and "exterior" Hill's regions and other resonant phenomena
The effect of falling home prices on small business borrowing
Small businesses continue to report problems in obtaining the financing they need. Because small business owners may rely heavily on the value of their homes to finance their businesses (through mortgages or home equity lines), the fall in housing prices might be one of the causes of their difficulty. We analyze information from a variety of sources and find that homes do constitute an important source of capital for small business owners and that the impact of the recent decline in housing prices is significant enough to be a real constraint on small business finances.Housing - Prices ; Small business - Finance
Crater population and resurfacing of the Martian north polar layered deposits
Present-day accumulation in the north polar layered deposits (NPLD) is thought to occur via deposition on the north polar residual cap. Understanding current mass balance in relation to current climate would provide insight into the climatic record of the NPLD. To constrain processes and rates of NPLD resurfacing, a search for craters was conducted using images from the Mars Reconnaissance Orbiter Context Camera. One hundred thirty craters have been identified on the NPLD, 95 of which are located within a region defined to represent recent accumulation. High Resolution Imaging Science Experiment images of craters in this region reveal a morphological sequence of crater degradation that provides a qualitative understanding of processes involved in crater removal. A classification system for these craters was developed based on the amount of apparent degradation and infilling and where possible depth/diameter ratios were determined. The temporal and spatial distribution of crater degradation is interpreted to be close to uniform. Through comparison of the size-frequency distribution of these craters with the expected production function, the craters are interpreted to be an equilibrium population with a crater of diameter D meters having a lifetime of ~30.75D^(1.14) years. Accumulation rates within these craters are estimated at 7.2D^(−0.14) mm/yr, which corresponds to values of ~3–4 mm/yr and are much higher than rates thought to apply to the surrounding flat terrain. The current crater population is estimated to have accumulated in the last ~20 kyr or less
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