Dairy farmers can change: results of a five-year national mastitis control program in The Netherlands

Over the years, much effort has been put into mastitis control programs. To further improve such programs, we need to understand farmers’ knowledge, attitude and behavior regarding udder health, and the way this can be influenced by mastitis control programs. This study aimed to explore the effect of a Dutch national mastitis control program on farmers’ knowledge, attitude and behavior regarding mastitis. In this study, 204 randomly selected dairy farmers completed a survey on attitude, knowledge and behavior regarding mastitis before the start of the national mastitis control program (2004) and in the final year of the program (2009). Statistical analyses show that, compared to 2004, the attitude, knowledge and behavior of the participating farmers changed significantly. Farmers’ satisfaction level and problem level of BMSCC changed; farmers were satisfied with on average 156,000 cells/ml in 2004 compared to 150,000 cells/ml in 2009, and perceived a problem at 285,000 cells/ml in 2004 compared to 271,000 cells/ml in 2009. More farmers perceived that they had sufficient knowledge about the control of mastitis (34% in 2004 vs. 53% in 2009), and they focused more often on udder health characteristics when selecting bulls (46% vs. 61%). Specific mastitis control measures have increased significantly during the program. The use of milking gloves increased from 15% to 46%, the use of a standardized mastitis treatment protocol increased from 7% to 34% and cubicles are cleaned more often (2.28 vs. 2.51 times/day)

Impact of Japanese Mergers on Shareholder Wealth: An Analysis of Bidder and Target Companies

The market for corporate control in the second largest economy in the world behaves very different from that in the U.S. Using a sample of 91 mergers in the period 1982-2003 we document several distinctive features of this market in Japan. First, we show that in stark contrast to the pro-cyclical U.S. merger waves, mergers in Japan tend to be counter-cyclical, both with respect to the general economy as well as with respect to stock market valuations. Second, and again in contrast to the U.S. experience, we find that a significant fraction of Japanese mergers are orchestrated by the main banks; in such cases, mergers are not between two weak companies, but at least one of the merging companies is financially strong. Other distinctive features of Japanese mergers are the positive pre-announcement returns accruing to both bidders and targets, with bidders capturing approximately half the gains that accrue to target firms. We also find differential shareholder wealth effects in the bubble period (1982-1989), the early 1990s, and the post-financial regulation regime (1997-2003). Overall our results point to a market for corporate control that is distinctly less shareholder-centered than that in the U.S. and one where creditors play an important, perhaps dominant, role.mergers;Japanse mergers;corporate control;take-over

A Wiener--Hopf Monte Carlo simulation technique for L\'{e}vy processes

We develop a completely new and straightforward method for simulating the joint law of the position and running maximum at a fixed time of a general L\'{e}vy process with a view to application in insurance and financial mathematics. Although different, our method takes lessons from Carr's so-called "Canadization" technique as well as Doney's method of stochastic bounds for L\'{e}vy processes; see Carr [Rev. Fin. Studies 11 (1998) 597--626] and Doney [Ann. Probab. 32 (2004) 1545-1552]. We rely fundamentally on the Wiener-Hopf decomposition for L\'{e}vy processes as well as taking advantage of recent developments in factorization techniques of the latter theory due to Vigon [Simplifiez vos L\'{e}vy en titillant la factorization de Wiener-Hopf (2002) Laboratoire de Math\'{e}matiques de L'INSA de Rouen] and Kuznetsov [Ann. Appl. Probab. 20 (2010) 1801--1830]. We illustrate our Wiener--Hopf Monte Carlo method on a number of different processes, including a new family of L\'{e}vy processes called hypergeometric L\'{e}vy processes. Moreover, we illustrate the robustness of working with a Wiener--Hopf decomposition with two extensions. The first extension shows that if one can successfully simulate for a given L\'{e}vy processes then one can successfully simulate for any independent sum of the latter process and a compound Poisson process. The second extension illustrates how one may produce a straightforward approximation for simulating the two-sided exit problem.Comment: Published in at http://dx.doi.org/10.1214/10-AAP746 the Annals of Applied Probability (http://www.imstat.org/aap/) by the Institute of Mathematical Statistics (http://www.imstat.org

Binding of metals to macromolecular organic acids in natural waters

Trace metal speciation and bioavailability have become keys to current day toxicity and risk assessments. For many metals, macromolecular organic acids constitute the major ligand in fresh water and soil solution. Therefore, understanding their characteristics and behaviour is necessary for understanding trace metal behaviour. This study comprises investigations of the proton- and copper-binding properties of hydrophobic and hydrophilic dissolved organic matter fractions, and competition effects of iron(III) and aluminium. The solutions studied were a forest floor solution and a municipal solid waste incinerator bottom ash leachate. Two geochemical models (SHM and NICA-Donnan) were tested and calibrated against the experimental data. A structural analysis of the binding mode of iron(III) to fulvic acid in acid aqueous solutions was made using extended X-ray absorption fine structure (EXAFS) spectroscopy. Dissolved organic carbon (DOC) in the bottom ash leachate had fulvic acid-like properties and was dominated by the hydrophilic acid fraction. Three organic fractions (hydrophobic, transphilic and hydrophilic) were isolated from the forest floor solution using an XAD-8/XAD-4 tandem. All fractions were characterised by distinct but differing proton-binding properties, suggesting a more acidic character than 'generic' fulvic acid. The copper-binding isotherms were very similar for all three fractions and suggested strong copper binding to a small number of sites. In general, both models tested could be adjusted to obtain good fits to data on both proton- and copper-binding, but iron(III) and aluminium competition was better predicted by the SHM than the NICA-Donnan model. Only mononuclear iron(III) complexes were included in the model calculations, as the EXAFS study showed that these ¬dominated in the aqueous phase. Studies on untreated soil solution indicated that the three isolated fractions were the only contributors to the observed copper binding and together constitute the 'active' DOC fraction. Thus, combination of Leenheer fractionation data with the model parameters derived in this study is recommended for improved predictions of trace metal speciation in soil solutions. However, further studies along this research line, including other samples and trace metals, are highly recommended

Judging From Experience: Experienced Sequences are Predicted Better than Described Sequences

When attempting to predict future events, people commonly rely on historical data. Events in a time series can be experienced sequentially (dynamic mode), as in learning about decisions from experience (e.g., Kusev et al., in press, JEP:HPP), or, as with learning about decisions from descriptions, they can also be retrospectively viewed holistically (static mode) – not experienced individually in real time. In one experiment, we studied the influence of presentation mode (dynamic and static) on three sorts of judgments: (i) predictions of the next event (forecast), (ii) estimation of the average value of all the events in the presented series (average) and (iii) judged satisfaction of workers given that the series represented their monthly income (satisfaction). Relative to the static mode participants‘ responses in dynamic mode were anchored on more recent events for all three types of judgments but with different consequences – hence dynamic presentation improved prediction accuracy, but not estimation

Security and privacy in online social networking: Risk perceptions and precautionary behaviour

A quantitative behavioural online study examined a set of hazards that correspond with security- and privacy settings of the major global online social network (Facebook). These settings concern access to a user's account and access to the user's shared information (both security) as well as regulation of the user's information-sharing and user's regulation of others' information-sharing in relation to the user (both privacy). We measured 201 non-student UK users' perceptions of risk and other risk dimensions, and precautionary behaviour. First, perceptions of risk and dread were highest and precautionary behaviour was most common for hazards related to users' regulation of information-sharing. Other hazards were perceived as less risky and less precaution was taken against these, even though they can lead to breaches of users' security or privacy. Second, consistent with existing theory, significant predictors of perceived risk were attitude towards sharing information on Facebook, dread, voluntariness, catastrophic potential and Internet experience; and significant predictors of precautionary behaviour were perceived risk, control, voluntariness and Internet experience. Methodological implications emphasise the need for non-aggregated analysis and practical implications emphasise interventions to promote safe online social-network use