p safedrop module to drop variables if and only if varnames specified in full p sampicc module to compute sample size for an intra-class correlation (ICC) p samplepps module to draw a random sample with probabilities proportional to size p samplesize module to execute sampsi multiple times and produce a graph p sampsi_fleming module to compute exact sample size calculation for single-stage designs p sampsi_mcc module to calculate Sample Size or Power for Matched Case-Control Studies p sampsi_reg module to calculate the sample size/power for linear regression p sampsi_rho module to compute sample size for a Pearson correlation p sampsi_sccs module to calculate the sample size for self controlled case series study designs p saswrapper module to run a SAS program from within Stata p savasas module to save your dataset as a SAS dataset p save9 module to save dataset in Stata 9 format p saveresults module to save output from a command in a file on disk p savesome module to save subset of data p sbbq module to implement the Harding and Pagan (2002) business cycle dating algorithm p sbplot module to generate scatter plot with one y variable shown by vertical bars p sbplot5 module to generate scatter plot with one y variable shown by vertical bars p sbri module to calculate the Spearman-Brown reliability p sbrowni module to calculate Spearman-Brown reliability correction for test length p scat3 module for crude three-dimensional graphics p scenreg module for estimating effects in models for binary variables given a scenario concerning unobserved variables p scheme_rbn1mono module to provide a minimal monochrome graphics scheme p scheme_tufte module to provide a Tufte-inspired graphics scheme p scls module to perform symmetrically censored least squares p scm module to process data for Social Cognitive Mapping p scoregof module to perform Score test of normality for probit and bivariate probit p scores module to calculate scores of variables depending on user specified number of missings p scsomersd module to compute rank statistics for scenario comparisons p sdecode module to decode a numeric variable into a string variable p sdlim module to rescale variables measured with a limited rating scale p sdline module to plot SD line or reduced major axis p sdtest modules (corrected) sdtest, sdtesti p seast module to calculate tests for seasonality with a variable population at risk p seg module to compute multiple-group diversity and segregation indices p segregation module to compute segregation indices p seldum module to transform indicator variables coefficients in semilog model p selectvars module for selecting all possible n-tuples from a varlist p semean module to compute standard error of mean (optionally from transformed data) p sencode module to encode a string variable non-alphanumerically into a numeric variable p sensatt module to compute sensitivity for matching estimators p senspec module to compute sensitivity and specificity results saved in generated variables p seq module to generate sequences of integers p seqlogit module to fit a sequential logit model p setpoisson module to estimate a Selection Endogenous Treatment Poisson model by MSL p setrngseed module to to set random-number seed using truly random integer from random.org p sf36 module to calculate summary statistics for the SF-36 Health Survey Instrument p sf36v2 module to score Short-Form 36 version 2 p shapley module to perform additive decomposition of sample statistic p sheafcoef module to compute sheaf coefficients p shortdir module to return the short Windows directory path name p shorth module for descriptive statistics based on shortest halves p showgph module to to show graphs previously saved p shownear module to show nearby values of numeric variable p shp2dta module to converts shape boundary files to Stata datasets p shuffle module to shuffle a list p shuffle8 module to shuffle a list p shufflevar module to shuffle variables relative to the rest of the dataset p sigcoef module to count statistically significant coefficients across models p sim_arma module to simulate data for ARMA processes p simirt module to process data generated by IRT models p simon2stage module to to compute the design parameters for a Simon two-stage design p simsum module to perform analyses of simulation studies including Monte Carlo error p simuped module to simulate two- and three-generation family data p singleb module to compute Contingent Valuation using Single-Bounded Dichotomous Choice p sixplot module to display six diagnostic and descriptive graphs for a single variable p sizefx module to compute effect size correlations p skbim module to generate a sample from a bimodal distribution using normal or skewed (skew-normal) unimodal distributions, as defined by the user p skewplot module to draw skewness plots p skilmack module to calculate Skillings-Mack statistic p sknor module to generate a sample from a normal or skewed (skew-normal) distribution, as defined by the user p skprobit module to perform Lagrange Multiplier Test for Normality for Probit model p sliceplot module for time series or other plot in slices p slideplot module for sliding bar plot for frequencies or percents p slideviewer module to manage linked SMCL presentations p slist module to "smart list" variables in compact format p smfit module to fit a Singh-Maddala distribution by maximum likelihood p smgfit module to fit a Singh-Maddala distribution to grouped data via ML p smhsiao module to conduct Small-Hsiao test for IIA in multinomial logit p smileplot module to create plots for use with multiple significance tests p smithwelch module to compute trend decomposition of outcome differentials p smwoodbury module to compute Sherman-Morrison-Woodbury rank-k update to matrix inverse p soepdo module to handle SOEP drop-outs p soepren module providing easy SOEP renames p soepuse module providing easy SOEP access p somersd module to calculate Kendall's tau-a, Somers' D and median differences p soreg module to implement the stereotype ordinal regression model p sortl module to sort factor loadings or rotated matrix from PCA or factor p sortlistby module to sort by random or by ancillary numlist p sortobs module to sort observations according to a specified order p sortrows program to perform sort within observation p spaces module to parse a file for delimiters p spagg module to create aggregate source or target contagion spatial effect variable for directed dyadic data p sparl module to produce scatter plot and y-x regression line p spautoc modules to calculate spatial autocorrelation (Moran and Geary measures) p spautoreg module to estimate Spatial (Lag-Error-Durbin-SAC-SPGKS-SPGSAR-GS2SLS-GS3SLS-SPML-SPGS-SPIVREG-IVTobit) p spcs2xt module to Convert Cross Section to Panel Spatial Weight Matrix p spdir module to create directed dyad contagion spatial effect variable p spearman2 module to calculate Spearman rank correlations, extended p spec_stand module to create dataset of stratum-specific, unadjusted and standardized rates p spell module for identification of spells or runs of similar values p spellutil module of utilities for the manipulation of timespan data p spglsxt module to estimate Spatial Panel Autoregressive Generalized Least Squares Regression p spgrid module to generate two-dimensional grids for spatial data analysis p sphdist module to compute spherical distances p spike module to allow for a zero willingness to pay p spikeplt module to generate spike plot showing fine structure of the data p spineplot module for spine plots for two-way categorical data p spkde module to perform kernel estimation of density and intensity functions for two-dimensional spatial point patterns p splagvar module to generate spatially lagged variables, construct the Moran Scatter plot, and calculate Moran's I statistics p split modules for splitting string variables into parts p splitvallabels module to split up value labels for multi-line graph labelling p spmap module to visualize spatial data p spmlreg module to estimate the spatial lag, the spatial error, the spatial durbin, and the general spatial models by maximum likelihood p spmon module to create spatial effect variable for monadic data p spmstar module to Estimate (m-STAR) Spatial Multiparametric Spatio Temporal AutoRegressive Regression Models p spmstarxt module to Estimate (m-STAR) Spatial Panel Multiparametric Spatio Temporal AutoRegressive Regression Models p sppack module for cross-section spatial-autoregressive models p sproper module to get proper case for foreign names in variables p spseudor2 module to calculate goodness-of-fit measures in spatial autoregressive models p spspc module to create specific source or target contagion spatial effect variable for directed dyadic data p spsurv module to fit split population survival ('cure') model p spundir module to create directed dyad contagion spatial effect variable p spweight module to compute Cross Section Spatial Weight Matrix p spweightcs module to compute Cross Section Spatial Weight Matrix p spweightxt module to compute Panel Spatial Weight Matrix p spwmatfill module to assign first nearest neighbors to observations with no contiguous neighbors p spwmatrix module to generate, import, and export spatial weights p spxttobit module to estimate Tobit Spatial Panel Autoregressive Generalized Least Squares Regression p sq module for sequence analysis p sqr module to make graphs square, or any other shape p sratio module to calculate ratio study statistics p sscsubmit module -- some notes on SSC Archive use for Stata users p ssi module to estimate sample size for randomized controlled trials p ssizebi module to calculate sample size and power for the comparison of two or more proportions p sskapp module to compute sample size for the kappa-statistic measure of interrater agreement p sslope module to calculate slope coefficients for regression interactions p ssm program to estimate endogenous switching and sample selection models for binary, count, and ordinal variables using ML p sssplot module to generate seasonal subseries plots p stack module to stack datasets p stak module to do simple reshapes or stacks p starjas module to produce Arjas plot to check proportional hazards assumption p stat2data module to generate a Dataset of Descriptive Statistics Calculated for a List of Variables p stata2pajek module to export data to Pajek .net format p statplot module for plots of summary statistics, including by category p statsbyfast module to efficiently compute statistics for by-group p statsmat module to place descriptive statistics in matrix p stbget module to get packages from Stata Technical Bulletin p stbtcalc module to calculate time-varying regression coefficients in Cox PH models p stcascoh module to create dataset suitable for case-cohort analysis p stcband module to compute Equal precision and Hall-Wellner confidence band for survival function p stcmd module to execute StatTransfer command from within Stata p stcompadj module to estimate the covariate-adjusted cumulative incidence function in the presence of competing risks p stcompet module to generate cumulative incidence in presence of competing events p stcoxgof module to produce goodness-of-fit test and plot after a Cox model p stcoxplt module to plot predicted survival curves from Cox model p stcstat module to generate evaluation of fit for Cox regression model p stcstat2 module to compute Harrell's c-index for flexible parametric models p stcumh module to check proportional hazards assumption p stexpect module to compute expected survival p stgtcalc module to calculate time-varying regression coefficients in Cox PH models (variant) p stjm module to fit shared parameter joint models of longitudinal and survival data p stjmgraph module to create a joint longitudinal and survival graph p stkerhaz module to produce baseline hazard estimates via kernel smoother and plots p stmix module to fit two-component parametric mixture survival models p sto module to toggle trace switch p stockcapit module to calculate physical capital stock by the perpetual-inventory method p stockquote module to retrieve stock quotes to a Stata-formatted dataset p storecmd modules to store and repeat commands using characteristics p stpepemori module to test the equality of cumulative incidences across two groups in the presence of competing risks p stpiece module to estimate piecewise-constant hazard rate models p stpm module to fit flexible parametric models for survival-time data p stpm2 module to estimate flexible parametric survival models p stpm2cif module to estimate cumulative incidence function after running stpm2 p stpm2cm module for estimation of crude mortality after fitting stpm2 relative survival model p stquant module to estimate quantiles for survival time p str2d module to compute explained variation for survival models p strdate module to replace string date variables with numeric date variables with the same names p strgen module to generate string variables without knowing string type p strgroup module to match strings based on their Levenshtein edit distance p strip module to strip unwanted characters p stripplot module for strip plots (one-way dot plots) p strparse module to parse string variables p strrec module to recode string variables according to rules p strsrcs module to fit flexible parametric models for relative survival using restricted cubic splines p stselpre module to fit proportional hazards model to case-cohort data p stsurvdiff module to compute difference in Kaplan-Meier survival curves p stsurvimpute module for flexible imputation of censored survival data p studysi module to calculates sample size and power for comparative studies p stylerules module -- suggestions on programming style p subsave module to save a subset of the dataset in memory to a disk file p sum2 module to store summary statistics p sumdist module to calculate summary statistics for income distributions p summdate module for summarizing date variable p summout module to produce comparative table of summary statistics p summvl module to generate summary table with variable labels (version 5) p sunflower module to generate density distribution sunflower plots p supclust module to build superordinate categories p surface module to draw a 3D wireform surface plot p survsim module to simulate complex survival data p survtime module to compute survival time for use in stset p survwgt module to create and manipulate survey weights p sutex module to LaTeX code for summary statistics tables p svmatf module to save a matrix to a file p svr module to compute estimates with survey replication (SVR) based standard errors p svret module to save returned results to your dataset p svvarlbl module to save variable labels to a file p svybsamp2 module to perform re-sampling for complex survey data p svygei_svyatk module to derive the sampling variances of Generalized Entropy and Atkinson inequality indices when estimated from complex survey data p svylorenz module to derive distribution-free variance estimates from complex survey data, of quantile group shares of a total, cumulative quantile group shares p svypxcat module to calculate predicted means or proportions for nominal X's for survey data p svypxcon module to calculate predicted means or proportions for a continuous X variable for survey data p svyselmlog module to compute selectivity adjustment based on the multinomial logit for survey design p svytabs module to Create Tables for export Combining Multiple Survey Tabulations p swapval module for swapping values of two variables p swblock module to perform parsimonious model selection in haplotype analysis p swboot module to bootstrap stepwise linear or logistic regression models p switch module to evaluate a given value against possible cases and their corresponding values p switchr module to estimate switching regression models p sxpose module to transpose string variable dataset p symmetry modules to perform tests of symmetry for NxN contingency tables p synth module to implement Synthetic Control Methods for Comparative Case Studies