Initial Public Offerings: The Case Of Health Maintenance Organizations (HMOs)

Objective: To determine whether the returns of initial public offerings (IPOs) of HMOs in the days following issue are similar to the return behavior of IPOs in previous studies.Data Source: The Center for Research in Security Prices (CRSP) tapes compiled by the Graduate School of Business at the University of Chicago provides daily stock prices, holding period returns, and other data pertinent to research in traded securities.Study Design: The hypothesis to be tested is whether the mean excess return surrounding the offer date is equal to zero.  To adjust the initial returns of the IPOs for overall market movements, Standard & Poor’s Composite Index (S&P 500) was selected as the proxy for the market in general.  We compute the long-run performance for the HMOs and compare that return to the S&P 500 and the CRSP AMEX/NYSE equally-weighted and value-weighted indices.Data Collection/Extraction Method:  We matched for-profit HMOs listed in the National Directory of Managed & Integrated Care Organizations to the commitment offerings reported by Securities Data Corporation to the same firms on the daily CRSP tapes.  This left 49 firms that went public between 1971 through 1997.  The Wharton Research and Data Services External (WRDSX) was used for data extraction and SAS was used for statistical analysis.Principal Findings: IPOs of HMOs are underpriced and demonstrate abnormal returns.  The average initial return on these IPOs is less than that of the average in the United States.  On a long-run performance basis, they performed better than the broad market indices.Conclusions:  Returns follow a similar pattern as do IPOs in general except for the long-run performance.  This needs further research as well as a comparison of performance before and after going public in cases where accounting data is available

Motivasi Belajar Siswa dalam Pembelajaran Pendidikan Jasmani Olahraga dan Kesehatan Siswa Sman 1 Tanah Putih Kecamatan Tanah Putih

, The background of the problem in this study originated from the observation while the researchers did the students of SMAN 1 Tanah Putih, researchers found differences in the motivation of siswa in physical education learning. Of these differences the researchers intend to seek to know what the real motivation of students through the study. Therefore, the purpose of this study was to determine how the student's motivation in physical education learning at SMAN 1 Tanah Putih. The research data was obtained from the distribution questionnaire filled by the sample. The sample in this study were students keals XI IPA 1 of 20 people (purposive sampling). Based on the research results can be concluded as follows: students' motivation to learn that the motivation of SMA Negeri 1 Tanah Putih Tanah Putih still have poor motivation. This means that to get a good learning outcomes one of its factors is motivation. The better aperson's motivation, the better the learning results obtained

Kontribusi Kelincahan dan Daya Tahan (Vo2max) dengan Keterampilan Menggiring Bola pada Tim Sepakbola Putra Smk Muhammadiyah 2 Pekanbaru

Agility and endurance is a skill which is football player must have. This study aims to find out how big the contribution of agility and endurance with dribbling skills of SMK Muhamadiyah 2 Pekanbarufootball team. The sample in this study amounted to 20 peoples with sampling technique of total sampling. Instrument agility with dodging run, endurance with bleep test, and dribble. At the time of analysis, there are some problems that occur such as at the time of dribbling, the ball loose control on the mastery, and the difficulty to break through the opponent's defense. Based on the results of the study, the data shows that there are contribution of agility, endurance, or combined both (agility and endurance) to the students' skills in dribbling. Percentage of agility, endurance, and agility and endurance of SMK. Muhamadiyah 2 Pekanbaru football team, each of which amounted to 45.74%, 28.30%, And 54.87%

Kontribusi Kelincahan dan Daya Tahan dengan Keterampilan Menggiring Bola pada Tim Sepakbola Smk Muhammadiyah 2 Pekanbaru

Agility and endurance is a skill which is football player must have. This study aims to find out how big the contribution of agility and endurance with dribbling skills of SMK Muhamadiyah 2 Pekanbarufootball team. The sample in this study amounted to 20 peoples with sampling technique of total sampling. Instrument agility with dodging run, endurance with bleep test, and dribble. At the time of analysis, there are some problems that occur such as at the time of dribbling, the ball loose control on the mastery, and the difficulty to break through the opponent's defense. Based on the results of the study, the data shows that there are contribution of agility, endurance, or combined both (agility and endurance) to the students' skills in dribbling. Percentage of agility, endurance, and agility and endurance of SMK. Muhamadiyah 2 Pekanbaru football team, each of which amounted to 45.74%, 28.30%, And 54.87%

AN IMPROVEMENT OF CROSS ENTROPY THRESHOLDING FOR SKIN CANCER

Image processing procedures in medical diagnosis are used to improve diagnosis accuracy. An example of this is skin cancer detection using the thresholding approach. Thus, research studies involved in identification of inherited mutations predisposing family members to malignant melanoma have been performed in the Cancer Genetics field. Melanoma is one of the deadliest cancers, but could be cured when diagnosed early. A fundamental step in image processing is segmentation that includes thresholding, among others. Thresholding is based on finding the optimal thresholds value that partitions the image into multiple classes to be able to distinguish the objects from the background. The algorithm developed in this work is based on Minimum Cross Entropy Thresholding (MCET) method, using statistical distributions. We improved the previous work of Pal by using separately different statistical distributions (Gaussian, Lognormal and Gamma) instead of Poisson distribution. We applied our improved methods on bimodal skin cancer images and obtained promising experimental results. The resulting segmented skin cancer images, using Gamma distribution yielded better estimation of the optimal threshold than does the same MCET method with Lognormal, Gaussian and Poisson distribution

Visualizing Structural Balance in Signed Networks

Network visualization has established as a key complement to network analysis since the large variety of existing network layouts are able to graphically highlight different properties of networks. However, signed networks, i.e., networks whose edges are labeled as friendly (positive) or antagonistic (negative), are target of few of such layouts and none, to our knowledge, is able to show structural balance, i.e., the tendency of cycles towards including an even number of negative edges, which is a well-known theory for studying friction and polarization. In this work we present Structural-balance-viz: a novel visualization method showing whether a connected signed network is balanced or not and, in the latter case, how close the network is to be balanced. Structural-balance-viz exploits spectral computations of the signed Laplacian matrix to place network's nodes in a Cartesian coordinate system resembling a balance (a scale). Moreover, it uses edge coloring and bundling to distinguish positive and negative interactions. The proposed visualization method has characteristics desirable in a variety of network analysis tasks: Structural-balance-viz is able to provide indications of balance/polarization of the whole network and of each node, to identify two factions of nodes on the basis of their polarization, and to show their cumulative characteristics. Moreover, the layout is reproducible and easy to compare. Structural-balance-viz is validated over synthetic-generated networks and applied to a real-world dataset about political debates confirming that it is able to provide meaningful interpretations

Slow Schroedinger dynamics of gauged vortices

Multivortex dynamics in Manton's Schroedinger--Chern--Simons variant of the Landau-Ginzburg model of thin superconductors is studied within a moduli space approximation. It is shown that the reduced flow on M_N, the N vortex moduli space, is hamiltonian with respect to \omega_{L^2}, the L^2 Kaehler form on \M_N. A purely hamiltonian discussion of the conserved momenta associated with the euclidean symmetry of the model is given, and it is shown that the euclidean action on (M_N,\omega_{L^2}) is not hamiltonian. It is argued that the N=3 flow is integrable in the sense of Liouville. Asymptotic formulae for \omega_{L^2} and the reduced Hamiltonian for large intervortex separation are conjectured. Using these, a qualitative analysis of internal 3-vortex dynamics is given and a spectral stability analysis of certain rotating vortex polygons is performed. Comparison is made with the dynamics of classical fluid point vortices and geostrophic vortices.Comment: 22 pages, 2 figure

Steady Stokes flow with long-range correlations, fractal Fourier spectrum, and anomalous transport

We consider viscous two-dimensional steady flows of incompressible fluids past doubly periodic arrays of solid obstacles. In a class of such flows, the autocorrelations for the Lagrangian observables decay in accordance with the power law, and the Fourier spectrum is neither discrete nor absolutely continuous. We demonstrate that spreading of the droplet of tracers in such flows is anomalously fast. Since the flow is equivalent to the integrable Hamiltonian system with 1 degree of freedom, this provides an example of integrable dynamics with long-range correlations, fractal power spectrum, and anomalous transport properties.Comment: 4 pages, 4 figures, published in Physical Review Letter

Measuring the mixing efficiency in a simple model of stirring:some analytical results and a quantitative study via Frequency Map Analysis

We prove the existence of invariant curves for a $T$--periodic Hamiltonian system which models a fluid stirring in a cylindrical tank, when $T$ is small and the assigned stirring protocol is piecewise constant. Furthermore, using the Numerical Analysis of the Fundamental Frequency of Laskar, we investigate numerically the break down of invariant curves as $T$ increases and we give a quantitative estimate of the efficiency of the mixing.Comment: 10 figure