# Class `"stsubpop"` This is the S4 class for stepp subpopulation object. The subpopulations are generated based on the stepp windows and the covariate of interest. 1.3 class ## Objects from the Class Objects can be created by calls of the form `new("stsubpop")` or the constructor method stepp.subpop. ## Slots - **`win`:**: Object of class `"stwin"` the stepp window set up for the analysis - **`covar`:**: Object of class `"numeric"` the covariate of interest - **`nsubpop`:**: Object of class `"numeric"` the number of subpopulations generated - **`subpop`:**: Object of class `"ANY"` a matrix of subpopulations generated based on the stepp window and the specified covariate of interest - **`npatsub`:**: Object of class `"numeric"` a vector of size of each subpopulation - **`medianz`:**: Object of class `"numeric"` a vector of median value of the covariate of interest for each subpopulation - **`minc`:**: Object of class `"numeric"` a vector of the minimum value of the covariate of interest for each subpopulation - **`maxc`:**: Object of class `"numeric"` a vector of the maximum value of the covariate of interest for each subpopulation - **`neventsubTrt0`:**: Object of class `"numeric"` or `NULL` a vector containing the number of events in each subpopulation for the baseline treatment group - **`neventsubTrt1`:**: Object of class `"numeric"` or `NULL` a vector containing the number of events in each subpopulation for the active treatment group - **`init`:**: Object of class `"logical"` a logical value indicating if the subpopulations have already been generated or not ## Methods - **generate**: `signature(.Object = "stsubpop", win, covariate, coltype, coltrt, trts,minsubpops)`: a method to generate the subpopulations based on the stepp window object and the specified covariate of interest. For event-based windows, also the event type (`coltype`), treatment indicator (`coltrt`), treatments list (`trts`) and minimum number of subpopulations (`minsubpops`) must be provided - **summary**: `signature(.Object = "stsubpop")`: a method to display the summary of the subpopulations generated ## Author(s) Wai-Ki Yip ## See Also `stwin`, `stmodelKM`, `stmodelCI`, `stmodelGLM`, `steppes`, `stmodel`, `stepp.win`, `stepp.subpop`, `stepp.KM`, `stepp.CI`, `stepp.GLM`, `stepp.test`, `estimate`, `generate` ## Examples ```r showClass("stsubpop") # create a steppp window win1 <- stepp.win(type="sliding", r1=5,r2=10) # generate the covariate of interest Y <- rnorm(100) # create and generate the stepp subpopulation sp <- new("stsubpop") sp <- generate(sp, win=win1, cov=Y) summary(sp) # event-based windows using the BIG data set data(bigKM) rxgroup <- bigKM$trt time <- bigKM$time evt <- bigKM$event cov <- bigKM$ki67 swin_e <- new("stwin", type = "sliding_events", e1 = 10, e2 = 20) subp_e <- new("stsubpop") subp_e <- generate(subp_e, win = swin_e, covariate = cov, coltype = evt, coltrt = rxgroup, trts = c(1, 2), minsubpops = 5) summary(subp_e) ```

stsubpop-class function