In the treatment of superficial lesions with 8-13 MeV electrons, lead shields are often used to protect the underlying tissue. Measurements were made with film and ion chamber to analyse various aspects of external and internal shielding in electron beam therapy. Data were obtained on the thickness of lead required for shielding, the effect of blocking on dose-rate, electron-backscattering from...

Mismatch negativity (MMN) is measured by subtracting the averaged response to a set of standard stimuli from the averaged response to rarer deviant stimuli, and taking the amplitude of this difference wave in a given time window. This method is problematic when used to evaluate individuals, because there is no estimate of variance. We describe a new approach, in which independent components wit...

Two R packages for sensitivity analysis in observational studies are described. Package sensitivitymw is for matched pairs with one treated subject and one control, or matched sets with one treated subject and a fixed number, K ≥ 2, of controls. Package sensitivitymv is for matched sets with variable numbers of controls. The packages offer conventional statistics, such as the permutational t-te...