Stata是一款完整的、集成的统计软件包，提供您需要的一切数据分析、数据管理和图形。
快速,简单并易于使用
点击式的界面和强大,直观的命令语言让Stata使用起来快速,精确并易于使用。
所有的分析结果都可以被复制和存档，并用来出版和审查。不管您什么时候写的内容，版本控制系统确保统计程序可继续生成同样的结果。
Stata的统计功能很强，除了传统的统计分析方法外，还收集了近20年发展起来的新方法，如Cox比例风险回归，指数与Weibull回归，多类结果与有序结果的logistic回归，Poisson回归，负二项回归及广义负二项回归，随机效应模型等。具体说， Stata具有如下统计分析能力：
数值变量资料的一般分析：参数估计，t检验，单因素和多因素的方差分析，协方差分析，交互效应模型，平衡和非平衡设计，嵌套设计，随机效应，多个均数的两两比较，缺项数据的处理，方差齐性检验，正态性检验，变量变换等。
分类资料的一般分析：参数估计，列联表分析 ( 列联系数，确切概率 ) ，流行病学表格分析等。
等级资料的一般分析：秩变换，秩和检验，秩相关等
相关与回归分析：简单相关，偏相关，典型相关，以及多达数十种的回归分析方法，如多元线性回归，逐步回归，加权回归，稳键回归，二阶段回归，百分位数 ( 中位数 ) 回归，残差分析、强影响点分析，曲线拟合，随机效应的线性回归模型等。
其他方法：质量控制，整群抽样的设计效率，诊断试验评价， kappa等。
使用Mata进行矩阵编程
Mata是一个成熟的编程语言，可编译您所输入的任何字节，并进行优化和准确执行。
尽管您不需要使用Stata进行编程，但是它作为一个快速完成矩阵的编程语言，是Stata功能中不可或缺的一部分。Mata既是一个操作矩阵的互动环境，也是一个完整开发环境，可以生产编译和优化代码。它还包含了一些特殊功能来处理面板数据、执行真实或复制的矩阵运算，提供完整的支持面向对象的编程，并完全兼容Stata。
跨平台兼容
Stata可在Windows，Mac和Linux/Unix电脑上运行，但是license不需要区分电脑系统。也就是说，如果您有一台Mac系统的电脑和一台Windows系统的电脑，您不需要2个license来运行Stata。您可以安装在任意支持的系统中安装Stata软件。Stata数据集、程序以及其他的数据*翻译就可以跨平台的共享。您还可以从其他的统计软件、电子报表和数据库中轻松而快速的导入数据。
Stata 16 New in Bayesian analysis—Multiple chains, predictions, and more
Multiple chains.
Bayesian inference based on an MCMC (Markov chain Monte Carlo) sample is valid only if the Markov chain has converged. One way we can evaluate this convergence is to simulate and compare multiple chains.
The new nchains() option can be used with both the bayes: prefix and the bayesmh command. For instance, you type
. bayes, nchains(4): regress y x1 x2
and four chains will be produced. The chains will be combined to produce a more accurate final result. Before interpreting the result, however, you can compare the chains graphically to evaluate convergence. You can also evaluate convergence using the Gelman–Rubin convergence diagnostic that is now reported by bayes: regress and other Bayesian estimation commands when multiple chains are simulated. When you are concerned about noncovergence, you can investigate further using the bayesstats grubin command to obtain individual Gelman–Rubin diagnostics for each parameter in your model.
Bayesian predictions.
Bayesian predictions are simulated values from the posterior predictive distribution. These predictions are useful for checking model fit and for predicting out-of-sample observations. After you fit a model with bayesmh, you can use bayespredict to compute these simulated values or functions of them and save those in a new Stata dataset. For instance, you can type
. bayespredict (ymin:@min({_ysim})) (ymax:@max({_ysim})), saving(yminmax)
to compute minimums and maximums of the simulated values. You can then use other postestimation commands such as bayesgraph to obtain summaries of the predictions.
The dataset created by bayespredict may include thousands of simulated values for each observation in your dataset. Sometimes, you do not need all of these individual values. To instead obtain posterior summaries such as posterior means or medians, you can use bayespredict, pmean or bayespredict, pmedian. Alternatively, you may be interested in a random sample of the simulated values. You can use, for instance, bayesreps, nreps(100) to obtain 100 replicates.
Finally, you may want to evaluate model goodness of fit using posterior predictive p-values, also known as PPPs or as Bayesian predictive p-values. PPPs measure agreement between observed and replicated data and can be computed using the new bayesstats ppvalues command. For instance, using our earlier example
. bayesstats ppvalues {ymin} {ymax} using yminmax
尽管您不需要使用Stata进行编程，
但是它作为一个快速完成矩阵的编程
语言，是Stata功能中不可或缺的一部
分。Mata既是一个操作矩阵的互动环
境，也是一个完整开发环境，可以生
产编译和优化代码。它还包含了一些
特殊功能来处理面板数据、执行真实
或复制的矩阵运算，提供完整的支持
面向对象的编程，并完全兼容Stata。
Panel-data ERMs
Extended regression models (ERMs) were a big new feature last release. The ERM commands fit models that account for three common problems that arise in observational data—endogenous covariates, sample selection, and treatment—either alone or in combination.
In Stata 16, we introduce the xteregress, xteintreg, xteprobit, and xteoprobit commands for fitting panel-data ERMs. This means ERMs can now account for the three problems we mentioned above and for within-panel correlation. These new commands fit random-effects linear, interval, probit, and ordered probit regression models. They allow random effects in one or all equations, and they allow random effects to be correlated across equations.
Researchers from all disciplines who work with observational (nonexperimental) data are interested in ERMs and will be excited about the new panel-data versions of these commands. However, different disciplines talk about these models differently.
Above, we referred to the problems ERMs solve as endogenous covariates, sample selection, treatment, and within-panel correlation. While this terminology is common in some disciplines such as economics, other disciplines may use other terms.
• Instead of panel-data and within-panel correlation, researchers may ask for models for multilevel (two-level) data that account for within-group correlation.
• Instead of endogenous covariates, researchers may ask for methods of dealing with unobserved confounding or unmeasured confounding.
• Instead of sample selection, researchers may be concerned about trials with informative dropout, nonignorable nonresponse, or outcomes missing not at random (MNAR).
• Instead of treatment, researchers may ask about methods for causal inference or estimating average treatment effects (ATEs).
The important message is that all disciplines are interested in ERMs, but they often speak different languages.
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