To PB or not PB: making wikis work for your library

Library staff at Leeds Metropolitan University have recently launched a wiki to help them with the organisation of the information they need for their day-to-day enquiry and circulation duties. Here we outline the development of the project and the reasons behind choosing a wiki as the best format for this information

UK household portfolios

This paper presents a detailed analysis of the composition of household portfolios, usingboth aggregate and micro-data. Among the key findings are that:• Most household wealth is held in the form of housing and pensions. Over time, there hasbeen a shift away from housing towards financial assets, driven largely by the growth inlife and pension funds.• Liquid financial wealth (excluding life and pension funds) is not predominantly held inrisky form. By far the most commonly held asset is an interest-bearing account at a bankor building society account. Of people with positive (liquid) financial wealth, more thanhalf is held in savings accounts.• The importance of risky assets in an individual’s portfolio varies according to theircharacteristics. The unconditional portfolio share held in risky assets (i.e. averagedacross those with and without any risky assets) rises with both age and total financialwealth. However, most of the variation in unconditional portfolio shares is due todifferences in ownership rates as opposed to the proportion of the portfolio held in riskyassets. Looking only at the people within each wealth decile who have risky assets, theconditional portfolio share is relatively constant across wealth, suggesting a possible rolefor entry costs or other fixed costs in explaining portfolio holdings. Multivariate analysisshows that the conditional portfolio share in risky assets actually falls with age asclassical portfolio theory would predict.• Finally, the tax treatment of savings products has an effect on portfolio choice. Separateprobit regressions for the ownership of tax-favoured assets and similar assets without thetax exemption, show that, controlling for other factors, marginal tax rates are important in determining asset ownership. These results are in accordance with those found by Poterba in the US

Efficacy of laser preionization with a semiconductor source and propene addition

It is established that propene is an effective additive instabilising uv preionised CO2 TEA laser discharges: its effect being particularly pronounced with semiconductor-edge preionised lasers where the preionisation levels are shown to be low

Unconditional bases and strictly convex dual renormings

We present equivalent conditions for a space $X$ with an unconditional basis to admit an equivalent norm with a strictly convex dual norm

The environments of intermediate-redshift QSOs: 0.3 < z < 0.7

An angular correlation of low significance (2 sigma) is observed between 0.3 < z < 0.5 QSOs and V < 23 galaxies. Overall, the cross-correlation function between 82 intermediate-redshift (0.3 < z < 0.7), X-ray selected QSOs and V < 24 galaxies is investigated, but no signal is detected for the z > 0.5 QSOs. After converting to an excess of galaxies physically associated with the QSO, this lack of strong correlation is shown to be consistent with the clustering of normal galaxies at the same moderate redshifts. Combined with previous observations, these results imply that the environments of radio-quiet QSOs do not undergo significant evolution with respect to the galaxy population over a wide range of redshifts (0 < z < 1.5). This is in marked contrast to the rapid increase in the richness of the environments associated with radio-loud QSOs over the same redshift range.Comment: 12 pages, 8 figures, MNRAS TeX macro, to appear to MNRA

Evaluating search and matching models using experimental data

This paper introduces an innovative test of search and matching models using the exogenous variation available in experimental data. We take an off-the-shelf Pissarides matching model and calibrate it to data on the control group from a randomized social experiment. We then simulate a program group from a randomized experiment within the model. As a measure of the performance of the model, we compare the outcomes of the program groups from the model and from the randomized experiment. We illustrate our methodology using the Canadian Self-Sufficiency Project (SSP), a social experiment providing a time limited earnings supplement for Income Assistance recipients who obtain full time employment within a 12 month period. We find two features of the model are consistent with the experimental results: endogenous search intensity and exogenous job destruction. We find mixed evidence in support of the assumption of fixed hours of labor supply. Finally, we find a constant job destruction rate is not consistent with the experimental data in this context

Local Weather Signs

PDF pages: 1

Ion clustering in aqueous salt solutions near the liquid/vapor interface

Molecular dynamics simulations of aqueous NaCl, KCl, NaI, and KI solutions are used to study the effects of salts on the properties of the liquid/vapor interface. The simulations use the models which include both charge transfer and polarization effects. Pairing and the formation of larger ion clusters occurs both in the bulk and surface region, with a decreased tendency to form larger clusters near the interface. An analysis of the roughness of the surface reveals that the chloride salts, which have less tendency to be near the surface, have a roughness that is less than pure water, while the iodide salts, which have a greater surface affinity, have a larger roughness. This suggests that ions away from the surface and ions near the surface affect the interface in opposite ways.Comment: 10 pages, 5 figure