StatsMiniBlog: Z scores.

A recent journal club article, the exact nature of which is irrelevant, triggered a coffee-room discussion on the subject of z scores, which although often understood in relation to Bone Mineral Density reports are otherwise a statistical challenge. In particular the difficulties in interpreting them in a meaningful way were lamented by our team. […]

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StatsMiniBlog: Causal Analysis

A while back, we looked at propensity scores as a way of adjusting / controlling for confounders in non-randomised designs. Another approach is the hypothesis-driven estimation of an ‘instrumental variable’: a measurable feature which causes* an outcome to occur through the agency of another. Uh? In the olden days (before smartphones, WiFi and email addresses that […]

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