Although I looked up the R docs for survfit{survival}, I couldn't see any information on this syntax ~ 1 in the formula
survfit(Surv(time, status) ~ 1, data = lung).
Could someone please help to explain what ~ 1 generally means in R?
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Nemo
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2In this case it means "fit a single curve". See `?survfit.formula`. – neilfws Apr 11 '23 at 00:14
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2As a hint for how to find this - `?survfit.formula` is listed in the 'See Also' section at the bottom of the help page for `?survfit` – thelatemail Apr 11 '23 at 00:17
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Thanks, @neilfws, "fit a single curve" makes sense for that _cryptic_ syntax `~ 1`. – Nemo Apr 11 '23 at 00:23