... Xu, J., and Kalkstein, L (1997) Air pollution, weather and mortality in Philadelphia, In Particulate Air Pollution and Daily Mortality: Analyses of the Effects of Weather and Multiple Air Pollutants ... , uL ]t (Hastie and Tibshirani, 1990; Chambers and Hastie, 1992) In time series studies of air pollution and mortality, the assumption of linearity of the smooth component of model (1) is inadequate, ... Linear Models. ” Journal of the Royal Statistical Society Series B , 50, 413–436 Stieb, D., Judek, S., and Burnett, R (2002) “Meta-analysis of time- series studies of air pollution and mortality: ...