contained in the MAIDS Final Report note any difference in rear-end accidents or accidents during lane splitting. It is notable that the pre-crash motion of the motorcycle or scooter was lane-splitting in only 0.4% of cases, in contrast to the more common accident situations such as "Moving in a straight line, constant speed" 49.1% and "Negotiating a bend, constant speed" 12.1%. The motorcyclist was stopped in traffic prior to 2.8% of the accidents. Preliminary results from a study in the United Kingdom, conducted by the University of Nottingham for the Department for Transport, show that filtering is responsible for around 5% of motorcycle Killed or Seriously Injured (KSI) accidents. It also found that in these KSI cases the motorist is twice as likely to be at fault as the motorcyclist due to motorists "failing to take into account possible motorcycle riding strategies in heavy traffic". A very different form of research, where the capacity benefits are examined as well, 1500 powered two-wheelers were video tracked to calibrate an agent based model of movement between and along lanes, also included a Bayesian model calibrated to determine the choices made to move between lanes. This model provides a basis for measuring the risk levels of such choices, and late applications allowed the determination of the capacity gains (in terms of passenger car equivalent) from such movement once filtered to the front of the queue and in continuing non-intersection movements along stretches of road Belgian policy research company Transport & Mobility Leuven published a study in September 2011 investigating the effects that increased motorcycle usage would have on traffic flow and emissions and found that a 10% modal shift would result in a 40% reduction in commute time and a 6% reduction in total emissions. This calculation assumed that all motorcycles moved between lanes and the space used by them, called a passenger car equivalent (PCE), would be reduced to zero when traffic came to a complete standstill. It also assumed that motorcycles would overtake cars without hindering them during heavy congestion, and PCE would be between less than 0.5, approaching zero as traffic density increased. Debate over safety and benefits Proponents state that the practice relieves congestion by removing commuters from cars and gets them to use the unused roadway space between the cars, and that lane splitting also improves fuel efficiency and motorcyclists' comfort in extreme weather. In the US, transportation