Statistics and society: a study on the burden experienced by caregivers of patients with Alzheimer

The cost of caring for people with Alzheimer-type diseases is enormous. Caregivers experience emotional, physical and financial stress, and their demands are central to decisions on patient institutionalization. We hereby investigate the burden experienced by caregivers of Alzheimer patients in Cyprus. We explore whether burden is related to variables such as patient psychopathology, caregiver gender, income and level of education. Moreover, we examine if there is a significant difference in the level of burden, depression, or reaction to memory and behavior problems when patients live in the community or in institutions and if the level of burden is associated with the use of different coping strategies by caregivers. Various statistical techniques are implemented for the analysis and all the conclusions are discussed. This work was partially funded by the Cyprus Research Promotion Foundation

Non-universality of halo profiles and implications for dark matter experiments

We explore the cosmological halo-to-halo scatter of the distribution of mass within dark matter haloes utilizing a well-resolved statistical sample of clusters from the cosmological Millennium Simulation. We find that at any radius, the spherically averaged dark matter density of a halo (corresponding to the ‘smooth component') and its logarithmic slope are well described by a Gaussian probability distribution. At small radii (within the scale radius), the density distribution is fully determined by the measured Gaussian distribution in halo concentrations. The variance in the radial distribution of mass in dark matter haloes is important for the interpretation of direct and indirect dark matter detection efforts. The scatter in mass profiles imparts approximately a 25 per cent cosmological uncertainty in the dark matter density at the Solar neighbourhood and a factor of ∼3 uncertainty in the expected Galactic dark matter annihilation flux. The aggregate effect of halo-to-halo profile scatter leads to a small (few per cent) enhancement in dark matter annihilation background if the Gaussian concentration distribution holds for all halo masses versus a 10 per cent enhancement under the assumption of a lognormal concentration distribution. The Gaussian nature of the cluster profile scatter implies that the technique of ‘stacking' haloes to improve signal-to-noise ratio should not suffer from bia

The effect of twitter dissemination on cost of equity: A big data approach

Reducing information asymmetry between investors and a firm can have an impact on the cost of equity, especially in an environment or times of uncertainty. New technologies can potentially help disseminate corporate financial information, reducing such asymmetries. In this paper we analyse firms’ dissemination decisions using Twitter, developing a comprehensive measure of the amount of financial information that a company makes available to investors (iDisc) from a big data of firms’ tweets (1,197,208 tweets). Using a sample of 4131 firm-year observations for 791 non-financial firms listed on the US NASDAQ stock exchange over the period 2009–2015, we find evidence that iDisc significantly reduces the cost of equity. These results are pronounced for less visible firms which are relatively small in size, have a low analyst following and a small number of investors. Highly visible firms are less likely to benefit from iDisc in influencing their cost of equity as other communication channels may have widely disseminated their financial information. Our investigations encourage managers to consider the benefits of directly spreading a firm’s financial information to stakeholders and potential investors using social media in order to reduce firm equity premium (COE)

Chiral restoration of strange baryons

We review the results of a phenomenological model for cold and dense nuclear matter exhibiting a chiral phase transition. The idea is to model the quark-hadron phase transition under neutron star conditions within a single model, but without adding quark degrees of freedom by hand. To this end, strangeness is included in the form of hyperonic degrees of freedom, whose light counterparts provide the strangeness in the chirally restored phase. In the future, the model can be used for instance to compute the surface tension at the (first-order) chiral phase transition and to study the possible existence of inhomogeneous phases.Comment: 6 pages, 4 figures, contribution to proceedings of QCD@Work, 27-30 June 202

Hybrid wildebeest (Artiodactyla:Bovidae) provide further evidence for shared signatures of admixture in mammalian crania

The genus Connochaetes, Lichtenstein, 1814, contains two extant species, the blue wildebeest (C. taurinus, Burchell, 1823) and the black wildebeest (C. gnou, Zimmermann, 1780). In recent years, forced sympatry in confined areas within South Africa has led to interbreeding between these taxa and to fertile hybrid offspring. Here we report on a series of cranial characteristics of a hybrid wildebeest population culled at Spioenkop Dam Nature Reserve, KwaZulu-Natal, South Africa. Dental, sutural and horn morphological anomalies occur at high frequency within these animals. Similar cranial morphological anomalies have been shown in other mammalian hybrids and this study provides further evidence that such anomalies may characterise hybridisation more broadly across phylogenetically divergent mammalian groups, although the anomalies appear to differ in their expression across taxa. An increased ability to identify hybrids may also have important applications in the conservation of the endemic black wildebeest

Hybrid wildebeest (Artiodactyla:Bovidae) provide further evidence for shared signatures of admixture in mammalian crania

The genus Connochaetes, Lichtenstein, 1814, contains two extant species, the blue wildebeest (C. taurinus, Burchell, 1823) and the black wildebeest (C. gnou, Zimmermann, 1780). In recent years, forced sympatry in confined areas within South Africa has led to interbreeding between these taxa and to fertile hybrid offspring. Here we report on a series of cranial characteristics of a hybrid wildebeest population culled at Spioenkop Dam Nature Reserve, KwaZulu-Natal, South Africa. Dental, sutural and horn morphological anomalies occur at high frequency within these animals. Similar cranial morphological anomalies have been shown in other mammalian hybrids and this study provides further evidence that such anomalies may characterise hybridisation more broadly across phylogenetically divergent mammalian groups, although the anomalies appear to differ in their expression across taxa. An increased ability to identify hybrids may also have important applications in the conservation of the endemic black wildebeest