{smcl} {* 26apr2003}{...} {hline} help for {cmd:relyplot} {hline} {title:Reliability Plot} {p 6 21 2} {cmdab:relyplot} [{cmd:if} {it:exp}] [{cmd:in} {it:range}]{cmd:,} {cmdab:fra:ctions(}3,4,5,or 10{cmd:)} or {cmdab:gr:oups(}#{cmd:)} [{cmd:ci} {it:graph_options}] {title:Description} {p 4 6 4} {cmd:relyplot} examines reliability of predicted risks following a {cmd:logistic} model. It creates categories of predicted risk, divided either into {cmd:fractions}, e.g. tenths, or any number of equal size {cmd:groups} (percentiles). It then calculates proportions of observed "events" among subjects within similar predictive probability categories. These proportions are plotted against a diagonal line for perfect fit (observed=predicted). Deviations from the line indicate worse prediction in those categories. {cmd:relyplot} can be repeated on a new sample using logistic regression estimates from another sample. {title:Options required (must choose one only)} {p 4 8 2} {cmd:fractions(}#{cmd:)} -- divides predicted risk into fractional categories of risk. Only groups with observations are displayed. The following values are allowed: 3 -- divides risk groups into thirds (0-.33, .33-.67, .67-1.0) 4 -- divides risk groups into fourths (0-.25, .25-.50, .50-.75, etc.) 5 -- divides risk groups into fifths (0-.20, .20-.40, .40-.60, etc.) 10 -- divides risk groups into tenths (0-.10, .10-.20, .20-.30, etc.) {p 4 8 2} {cmd:groups(}#{cmd:)} -- divides predicted risk into percentiles, i.e., # of equal size groups; this would be useful if using fractions (see {cmd:fractions}) results in too few observations in some groups to accurately calculate observed risk {title:Options} {p 4 8 2} {cmd:ci} -- Plots the 95% confidence interval around the observed proportions {title:Examples} {cmd:. use sample1} {cmd:. logistic died chol age htn} {cmd:. relyplot, fractions(10)} Displays a reliabilitly plot with predicted risks divided into tenths {cmd:. use sample2} {cmd:. relyplot, fractions(10)} Opens a second data set, uses estimates from first data set {cmd:. relyplot, group(5)} Divides predicted risk into 5 equal size groups, i.e., quintiles