Suchergebnisse

Stata is the most flexible and extensible data analysis package available from a commercial vendor. R is a similarly flexible free and open source package for data analysis, with over 3,000 add-on packages available. This book shows you how to extend the power of Stata through the use of R. It introduces R using Stata terminology with which you are already familiar. It steps through more than 30 programs written in both languages, comparing and contrasting the two packages` different approaches. When finished, you will be able to use R in conjunction with Stata, or separately, to import data, manage and transform it, create publication quality graphics, and perform basic statistical analyses. A glossary defines over 50 R terms using Stata jargon and again using more formal R terminology. The table of contents and index allow you to find equivalent R functions by looking up Stata commands and vice versa. The example programs and practice datasets for both R and Stata are available for download. TOC:Introduction.- Installing and Updating R.- Running R.- Help and Documentation.- Programming Language Basics.- Data Acquisition.- Selecting Variables.- Selecting Observations.- Selecting Variables and Observations.- Data Management.- Enhancing Your Output.- Generating Data.- Managing Your Files and Workspace.- Graphics Overview.- Traditional Graphics.- Graphics with ggplot2.- Statistics.- Conclusion.

Change became the mantra of the 2008 presidential campaign. During the primaries, Senators Clinton, McCain and Obama, as well as Governor Huckabee, all used the idea of change as part of their campaign rhetoric. During the general election campaign, both Obama and McCain continued using change as their slogan. This study sought to determine what the youth vote believed that change meant, both in an overall sense and as attributed to each of the candidates. The data for Study 1 were conducted before the March 4, 2008, primary, and the data for Study 2 were collected in October 2008. In Study 1, 784 undergraduates from six states and nine colleges and universities participated. In Study 2, there were 260 undergraduates who participated. The findings in both studies reveal that the candidates were effective in their use of the word change , as the respondents were able to differentiate between the different campaign messages. Analysis of the open-ended data found several overall categories of change, and subsequent analysis found that these categories were more relevant to certain demographics than others. A discussion of the findings as well as ideas for future research is discussed.