The performance of the jet trigger for the ATLAS detector during 2011 data taking

The performance of the jet trigger for the ATLAS detector at the LHC during the 2011 data taking period is described. During 2011 the LHC provided proton–proton collisions with a centre-of-mass energy of 7 TeV and heavy ion collisions with a 2.76 TeV per nucleon–nucleon collision energy. The ATLAS trigger is a three level system designed to reduce the rate of events from the 40 MHz nominal maximum bunch crossing rate to the approximate 400 Hz which can be written to offline storage. The ATLAS jet trigger is the primary means for the online selection of events containing jets. Events are accepted by the trigger if they contain one or more jets above some transverse energy threshold. During 2011 data taking the jet trigger was fully efficient for jets with transverse energy above 25 GeV for triggers seeded randomly at Level 1. For triggers which require a jet to be identified at each of the three trigger levels, full efficiency is reached for offline jets with transverse energy above 60 GeV. Jets reconstructed in the final trigger level and corresponding to offline jets with transverse energy greater than 60 GeV, are reconstructed with a resolution in transverse energy with respect to offline jets, of better than 4 % in the central region and better than 2.5 % in the forward direction

Modifying beliefs and attitudes to exceeding the speed limit: An intervention study based on the theory of planned behavior

This study builds on previous theory of planned behavior (TPB) studies in which we identified the beliefs and values which predict intention to commit driving violations. Four short experimental videos were developed in order to assess the effectiveness of an intervention grounded in the TPB. Three of the videos featured the major constructs of the TPB model. The fourth video featured anticipated regret, an addition to the TPB model which had previously been shown to add significantly to its predictive performance (Parker, Manstead, & Stradling, 1995). Results indicated that two of the videos brought about statistically significant belief changes with respect to scores on TPB items, and significant changes in general attitudes toward speeding. Discussion centers on the problems encountered in operationalizing the TPB constructs and on the potential of theory-based interventions to induce attitude change

Behavioural characteristics and involvement in different types of traffic accidents

Recent research has shown risk of road traffic accident involvement to be associated with the tendency to commit driving violations, fast driving, and a lack of thoroughness in decision making. It has also been shown that three broad types of accident can be used to categorise more than 70% of drivers' brief written descriptions of their accidents. These categories are “shunts” (rear-end collisions), right-of-way violations, and loss-of-control accidents. Furthermore, for each accidenttype the role of the reporting driver may be defined as active (striking) or passive (struck) depending on the position of his/her vehicle. This paper reports two studies examining the extent to which measures of tendency to commit violations (measured by the Driver Behaviour Questionnaire (DBQ)), frequency of fast driving (measured by the Driving Style Questionnaire (DSQ)) and thoroughness in decision making (measured by the Decision Making Questionnaire (DMQ)) are associated specifically with involvement in each of the main accident types. The results showed that a high DBQ-violation score was associated with accidents in general, both active and passive, and specifically with active loss-of-control accidents and passive right-of-way accidents. High DSQ-speed and low DMQ-thoroughness were associated with active but not passive accidents, high DSQ-speed with active right-of-way violations, and low DMQ-thoroughness was specifically associated with active shunts and active right-of-way violations. The implications of these results are discussed