An accessible primer on how to create effective graphics from data This book provides students and researchers a hands-on introduction to the principles and practice of data visualization. It explains what makes some graphs succeed while others fail, how to make high-quality figures from data using powerful and reproducible methods, and how to think about data visualization in an honest and effective way. Data Visualization builds the reader's expertise in ggplot2, a versatile visualization library for the R programming language. Through a series of worked examples, this accessible primer then demonstrates how to create plots piece by piece, beginning with summaries of single variables and moving on to more complex graphics. Topics include plotting continuous and categorical variables; layering information on graphics; producing effective "small multiple" plots; grouping, summarizing, and transforming data for plotting; creating maps; working with the output of statistical models; and refining plots to make them more comprehensible. Effective graphics are essential to communicating ideas and a great way to better understand data. This book provides the practical skills students and practitioners need to visualize quantitative data and get the most out of their research findings. Provides hands-on instruction using R and ggplot2 Shows how the "tidyverse" of data analysis tools makes working with R easier and more consistent Includes a library of data sets, code, and functions

More than any other altruistic gesture, blood and organ donation exemplifies the true spirit of self-sacrifice. Donors literally give of themselves for no reward so that the life of an individual--often anonymous--may be spared. But as the demand for blood and organs has grown, the value of a system that depends solely on gifts has been called into question, and the possibility has surfaced that donors might be supplemented or replaced by paid suppliers.
"Last Best Gifts" offers a fresh perspective on this ethical dilemma by examining the social organization of blood and organ donation in Europe and the United States. Gifts of blood and organs are not given everywhere in the same way or to the same extent--contrasts that allow Kieran Healy to uncover the pivotal role that institutions play in fashioning the contexts for donations. Procurement organizations, he shows, sustain altruism by providing opportunities to give and by producing public accounts of what giving means. In the end, Healy suggests, successful systems rest on the fairness of the exchange, rather than the purity of a donor's altruism or the size of a financial incentive.