hzdsel
Period-two hazards after selective depletion
hzdsel(s, h, l, surh, surl)crimlab.hzdsel(s, h, l, surh, surl)crimlab hzdsel --s VALUE --h VALUE --l VALUE --surh VALUE --surl VALUEA share s of a cohort is at high risk of reconviction, h a period,
and the rest at low risk, l. If a programme changes who survives the
first period without reconviction, the period-two hazard among the
survivors is a weighted average of h and l with weight the share of
high-risk survivors, and it rises with that share. An arm that keeps
more of its high-risk people out of reconviction in period one therefore
shows the higher period-two hazard even if it has no effect on anyone in
period two: a period-by-period hazard ratio is not a causal contrast; a
risk difference at a fixed follow-up is. See proof("hzdsel").
Parameters
Section titled “Parameters”sThe high-risk share at the start, strictly between 0 and 1.
hThe period hazard of the high-risk type: at most 1.
lThe period hazard of the low-risk type: from 0, below
h.surhPeriod-one survival of the high-risk type in the control and treated arms: two numbers above 0 and at most 1, the control arm first, or named
controlandtreatedin either order (withsurlnamed too). A list of single numbers or a one-row data frame is accepted.surlPeriod-one survival of the low-risk type, the same way; named inputs are matched to
surhby name.
Returns
Section titled “Returns”A named numeric vector: share0, share1 (the high-risk share
among the survivors of each arm), haz0, haz1 (the period-two hazard
in each arm) and ratio (haz1 / haz0).
References
Section titled “References”Hernan, M. A. (2010). The hazards of hazard ratios. Epidemiology, 21(1), 13-15. doi:10.1097/EDE.0b013e3181c1ea43
Examples
Section titled “Examples”hzdsel(s = 0.5, h = 0.5, l = 0.1, surh = c(0.5, 0.8), surl = c(0.9, 0.9))Generated from the R help page: hzdsel in the R reference.