Interactive Correspondence Analysis in a Dynamic Object-Oriented Environment

A highly interactive, user-friendly object-oriented software package written in LispStat is introduced that performs simple and multiple correspondence analysis, and profile analysis. These three techniques are integrated into a single environment driven by a user-friendly graphical interface that takes advantage of Lisp-Stat's advanced graphical capabilities. Techniques that assess the stability of the solution are also introduced. Some of the features of the package include colored graphics, incremental graph zooming capabilities, manual point separation to determine identities of overlapping points, and stability and fit measures. The features of the package are used to show some interesting trends in a large educational dataset.

ada: An R Package for Stochastic Boosting

Boosting is an iterative algorithm that combines simple classification rules with "mediocre" performance in terms of misclassification error rate to produce a highly accurate classification rule. Stochastic gradient boosting provides an enhancement which incorporates a random mechanism at each boosting step showing an improvement in performance and speed in generating the ensemble. ada is an R package that implements three popular variants of boosting, together with a version of stochastic gradient boosting. In addition, useful plots for data analytic purposes are provided along with an extension to the multi-class case. The algorithms are illustrated with synthetic and real data sets.

Statistical Analysis of Financial Data in S-PLUS

Abstracts not available for BookReview

Experimental and numerical study of the response of the offshore combined wind/wave energy concept SFC in extreme environmental conditions

This paper deals with an experimental study of the survivability of the offshore combined concept Semisubmersible wind energy and Flap-type wave energy Converter (SFC) and with comparisons of the experimental data with numerical predictions. The SFC is a combined energy concept consisting of a braceless semisubmersible type floating wind turbine and three fully submerged rotating flap-type Wave Energy Converters (WECs). In order to study the survivability of the concept the focus is on extreme environmental conditions. In these conditions the SFC will not produce wind or wave power; the wind turbine is parked with the blades feathered into the wind and the WECs are released to freely rotate about their axis of rotation. Firstly the development and set-up of the physical model are presented. Static, quasi-static, decay, regular waves and irregular waves with wind loading tests are conducted on an 1:50 scale physical model. Aligned and oblique wave with wind loading conditions are considered. Measured variables that are presented include motions of the semisubmersible platform in six rigid body degrees of freedom, rotation of the flap-type WECs, tension of mooring lines, internal loads of the arms that connect the flap with the pontoon of the platform and tower base bending moment. The experimental data are compared with numerical predictions obtained by a fully coupled numerical model. The comparison is made at model scale. A good agreement between experimental data and numerical predictions is observed confirming the accuracy of the numerical models and tools that are used. The discrepancy between numerical and experimental results is smaller for regular than irregular waves. Compared to oblique conditions a better agreement between experimental and numerical results is obtained for the case of aligned wave and wind loadings. The results obtained demonstrate the good performance of the SFC concept in extreme environmental conditions. No strong nonlinear hydrodynamic phenomena are observed in the tests

Update of pistachio leaf spot caused by Septoria pistaciarum in light of new taxonomic advances in Italy.

Abstract Septoria leaf spot is one the most widespread disease affecting pistachio (Pistacia vera) in countries of the Mediterranean region. Traditionally, three species have been associated with pistachio, including Septoria pistaciae, Septoria pistaciarum and S. pistacina. However, recent taxonomic studies have reordered and clarified the status of Septoria and septoria-like pathogens affecting pistachio. In our study, field surveys conducted in the traditional Sicilian pistachio production area of Bronte revealed the presence of trees showing characteristic septoria-like leaf spot. Collected isolates were morphologically and molecularly characterized. Morphological characterization was based on conidia measurements and evaluation of mycelial growth on different artificial media. Tested media included CMA, MEA, OA, PDA, and SNA. Phylogenetic analysis was conducted on a multi-locus approach (ITS + tef1 + tub2) based on Maximum Parsimony and Maximum Likelihood. Results showed that our isolates clustered with S. pistaciarum. Pathogenicity test was conducted in the field using conidia suspensions in order to fulfill Koch's postulates. Presence of characteristic rounded spots and pycnidia was evaluated on the inoculated leaves 9 and 23 days after inoculation. This study represents the first update on S. pistaciarum in Italy since its first identification in 1934

Timing of initial public offerings, seasoned equity offerings and takeover bids financed with equity: UK evidence

This thesis examines the "timing" of equity issues. We seek to find the factors that "drive" the time series variation in the equity issuance activity. Our main motivation is to see whether the Initial Public Offerings, Seasoned equity offerings and Takeover activity financed with equity move together. Our second motivation is to see whether certain individual factors affect the timing of the three corporate activities. We focus our research effort on whether business conditions, adverse selection costs and "sentiment timing" can explain the variation in equity issue activity across time. Economic conditions have a significant effect on equity issuance activity. More firms make an IPO and more capital is raised from IPOs during the upturn of the business cycle relative to the downturn of the cycle. The impact of economic conditions on the SEO volume is also positive but marginally significant. In addition, more bidders use equity to finance a takeover bid during the upturn of the business cycle. The improvement of business conditions has a significant effect on the magnitude of adverse selection costs associated with the announcement of a SEO and a takeover bid that is financed with equity. During the upturn of the business cycle the market reacts less adversely to the announcement of these actions while in the downturn of the cycle the announcement of the SEO and the equity financed bid is accompanied by more negative returns. Underpricing for IPOs however is not lower during the upturn of the business cycle. Firms that make an IPO, a SEO and a takeover bid that is financed with equity are associated with significant adverse share price movements which impose significant indirect costs to the issuers and bidders. This thesis investigates how these costs affect the timing of the three corporate actions. The magnitude of adverse selection costs has a significant effect only on the volume of Seasoned equity offerings with more firms making a rights issue during periods when the announcement of the recent rights issues is accompanied by less negative returns. IPO volume is not higher when the average first day returns of the recent IPOs are low and the percentage of bidders that use equity to finance the bid over all bidders is not higher when the drop of the share price of the bidder on the announcement of the recent equity financed bids is smaller. It has been widely documented that firms which make an IPO, a SEO and a takeover bid that is financed with equity offer inferior returns to their shareholders in the post-issue period. Cognitive bias and deliberate timing of these actions at periods when share prices are irrationally high are the best explanations that the literature has provided for the underperformance. We find a significant underperformance of SEOs and bidders that use equity to finance the bid and IPOs if the high first day returns are not included. These findings suggest that the above firms are overvalued at the time these action take place but does not address whether variations in volume across time are driven by variation in the degree of overvaluation. We find that only variations in IPO volume are driven by variations in the degree of overvaluation. Periods when more capital is raised from IPOs are periods when the average IPO is more overvalued than IPOs that go public in periods when IPO activity slows down. Variations in the SEO volume and the equity financed takeover activity are not driven by overvaluation exploitation. Time series regressions on the amount raised from IPOs and SEOs reveals the significant role of investors' sentiment on the timing of equity issues. We use financial analysts earnings forecasts as a proxy for market sentiment and we find that more capital is raised from IPOs during periods when analysts' earnings forecasts for the recent IPOs are more optimistic. We also find that more capital is raised from SEOs during periods when analysts' earnings forecasts for the recent SEOs are more overoptimistic. Previous empirical studies suggest that firms time the issues at the peak of their profitability. Our evidence from financial analysts earnings forecast revisions reveal that SEO firms time the issue after a period of high earnings growth and prior to a small deterioration in earnings while IPO firms time the issue at the beginning or during a period of sustainable earnings growth and not at the peak of their profitability