CEO overconfidence and dividend policy

We develop a model of the effect of CEO overconfidence on dividend policy and empirically examine many of its predictions. Consistent with our main prediction, we find that the level of dividend payout is lower in firms managed by overconfident CEOs. We document that this reduction in dividends associated with CEO overconfidence is greater in firms with lower growth opportunities, lower cash flow, and greater information asymmetry. We also show that the magnitude of the positive market reaction to a dividend-increase announcement is lower for firms managed by overconfident CEOs. Our overall results are consistent with the predictions of our model.Chief executive officers ; Dividends

Cascades: A view from Audience

Cascades on online networks have been a popular subject of study in the past decade, and there is a considerable literature on phenomena such as diffusion mechanisms, virality, cascade prediction, and peer network effects. However, a basic question has received comparatively little attention: how desirable are cascades on a social media platform from the point of view of users? While versions of this question have been considered from the perspective of the producers of cascades, any answer to this question must also take into account the effect of cascades on their audience. In this work, we seek to fill this gap by providing a consumer perspective of cascade. Users on online networks play the dual role of producers and consumers. First, we perform an empirical study of the interaction of Twitter users with retweet cascades. We measure how often users observe retweets in their home timeline, and observe a phenomenon that we term the "Impressions Paradox": the share of impressions for cascades of size k decays much slower than frequency of cascades of size k. Thus, the audience for cascades can be quite large even for rare large cascades. We also measure audience engagement with retweet cascades in comparison to non-retweeted content. Our results show that cascades often rival or exceed organic content in engagement received per impression. This result is perhaps surprising in that consumers didn't opt in to see tweets from these authors. Furthermore, although cascading content is widely popular, one would expect it to eventually reach parts of the audience that may not be interested in the content. Motivated by our findings, we posit a theoretical model that focuses on the effect of cascades on the audience. Our results on this model highlight the balance between retweeting as a high-quality content selection mechanism and the role of network users in filtering irrelevant content

Tuning density profiles and mobility of inhomogeneous fluids

Density profiles are the most common measure of inhomogeneous structure in confined fluids, but their connection to transport coefficients is poorly understood. We explore via simulation how tuning particle-wall interactions to flatten or enhance the particle layering of a model confined fluid impacts its self-diffusivity, viscosity, and entropy. Interestingly, interactions that eliminate particle layering significantly reduce confined fluid mobility, whereas those that enhance layering can have the opposite effect. Excess entropy helps to understand and predict these trends.Comment: 5 pages, 3 figure

Effects of lengthscales and attractions on the collapse of hydrophobic polymers in water

We present results from extensive molecular dynamics simulations of collapse transitions of hydrophobic polymers in explicit water focused on understanding effects of lengthscale of the hydrophobic surface and of attractive interactions on folding. Hydrophobic polymers display parabolic, protein-like, temperature-dependent free energy of unfolding. Folded states of small attractive polymers are marginally stable at 300 K, and can be unfolded by heating or cooling. Increasing the lengthscale or decreasing the polymer-water attractions stabilizes folded states significantly, the former dominated by the hydration contribution. That hydration contribution can be described by the surface tension model, $\Delta G=\gamma (T)\Delta A$, where the surface tension, $\gamma$, is lengthscale dependent and decreases monotonically with temperature. The resulting variation of the hydration entropy with polymer lengthscale is consistent with theoretical predictions of Huang and Chandler (Proc. Natl. Acad. Sci.,97, 8324-8327, 2000) that explain the blurring of entropy convergence observed in protein folding thermodynamics. Analysis of water structure shows that the polymer-water hydrophobic interface is soft and weakly dewetted, and is characterized by enhanced interfacial density fluctuations. Formation of this interface, which induces polymer folding, is strongly opposed by enthalpy and favored by entropy, similar to the vapor-liquid interface.Comment: 24 pages, 5 figure

Decremental All-Pairs ALL Shortest Paths and Betweenness Centrality

We consider the all pairs all shortest paths (APASP) problem, which maintains the shortest path dag rooted at every vertex in a directed graph G=(V,E) with positive edge weights. For this problem we present a decremental algorithm (that supports the deletion of a vertex, or weight increases on edges incident to a vertex). Our algorithm runs in amortized O(\vstar^2 \cdot \log n) time per update, where n=|V|, and \vstar bounds the number of edges that lie on shortest paths through any given vertex. Our APASP algorithm can be used for the decremental computation of betweenness centrality (BC), a graph parameter that is widely used in the analysis of large complex networks. No nontrivial decremental algorithm for either problem was known prior to our work. Our method is a generalization of the decremental algorithm of Demetrescu and Italiano [DI04] for unique shortest paths, and for graphs with \vstar =O(n), we match the bound in [DI04]. Thus for graphs with a constant number of shortest paths between any pair of vertices, our algorithm maintains APASP and BC scores in amortized time O(n^2 \log n) under decremental updates, regardless of the number of edges in the graph.Comment: An extended abstract of this paper will appear in Proc. ISAAC 201

Cellulose based materials to accelerate the transition towards sustainability

Several significant sectors use cellulose, including paper manufacturing, cellophane, textiles (including rayon and viscose), and food and medicine additives. It can be utilised as a raw materials in production of fuel sources like cellulosic ethanol. Crystalline cellulose possesses a tensile strength of about 7.5 GPa, Young’s modulus of 110-220 GPa and as the most abundantly available natural polymer, with excellent biocompatibility, good degradation and regeneration properties, it is considered as a remarkable biomaterial. Cellulose-based materials can be fabricated with tuneable magnetic properties, electrical conductivity, photosensitivity, sensing abilities, catalytic activity, and other specific properties by incorporating nanoparticles. These qualities make cellulose a sustainable multifunctional material. To harness such properties, strenuous efforts are being made to manufacture cellulose based materials through a wide number of manufacturing processes. This review provides an overview of the current readiness in producing cellulose-based functional materials by surveying the manufacturing procedures, characteristics and their potential applications for the end users. Future directions and opportunities of work are suggested and the limitations inherent with every process and the challenges that needs to be overcome in scalable manufacturing of cellulose-based materials are also discussed

Construction of Health Infrastructure Index in Haryana: An Econometric Approach

The provision of health infrastructure is one of the major areas of concern in Indian economy including Haryana. Health infrastructure which comprises all the resources necessary to provide health services, is proved to be essential to create health human capital. Thus, being a merit good, establishment of health infrastructure is the prime duty of the State. With this backdrop, the present study is attempted to construct health infrastructure index for the State of Haryana. On the basis of the available data taken from various issues of Statistical Abstract of Haryana, fourteen indicators of health infrastructure are considered for the period of twenty one years from 1991-92 to 201112. First of all, the collected data is analyzed by computing descriptive statistics which reveal that seven indicators of health infrastructure possess positive compound annual growth rate (CAGR) while seven others have negative CAGR and certain indicators have experienced high variations in their number over the years. Next, normalization of data is done and then by applying principal component analysis (PCA), composite index for health infrastructure is constructed in various steps including correlation matrix, KMO measure and Bartlett’s test; eigenvalues of components; component loading matrix; calculation of weights for variables (indicators of health infrastructure) and finally health infrastructure index. As per index scores, ranks are given to the State for its health infrastructure for all twenty one years. It is found that health infrastructure in Haryana for the year 2004-05 have attained rank 1st with index score 1.000, followed by 2011-12 with score 0.837 and the year 2003-04 having the value of 0.764. Between 1991-92 and 2011-12, up and downs in index scores as well as in ranks are seen. Besides, score of health infrastructure index remain up to 0.5 for eleven years while above 0.5 for ten years. However, the year 200910 can be considered quite embarrassing for which score of health infrastructure index is zero indicating availability of health infrastructure was at lowest level in this year. Fortunately, the year 2011-12 having 2nd rank in health infrastructure index arises a ray of hope for the further promotion in the availability of health infrastructural facilities in coming years in State of Haryana. However, negative growth rates of certain indicators and low scores of health infrastructure index calls for immediate attention of Government with sufficient investments towards health infrastructure in Haryana. &nbsp