This graphic says "March Methodology Madness"

This Is R time

In our annual issue devoted to research methods and practices, we present a collection of articles on R statistical computing packages created by (and for) psychological scientists.

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Volume 30, Issue3March 2017

About the Observer

Published 6 times per year by the Association for Psychological Science, the Observer educates and informs on matters affecting the research, academic, and applied disciplines of psychology; promotes the scientific values of APS members; reports on issues of international interest to the psychological science community; and provides a vehicle for the dissemination on information about APS.

APS members receive the Observer newsletter and may access the online archive going back to 1988.

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    Myths and Misinformation

    How does misinformation spread and how do we combat it? Psychological science sheds light on the mechanisms underlying misinformation and ‘fake news.’


Up Front

  • This is a Portrait of Sian Beilock.

    Preparing Students for Diverse Careers in Our Science

    Psychological science shares borders with many diverse areas. Training in psychological science thus can prepare students to succeed not only in academic departments related to psychology, but also in nonacademic worlds. I asked my colleague Sian L. Beilock to describe the initiative that she is spearheading at the University of Chicago — UChicagoGRAD — which is dedicated to teaching PhD students, including students of psychological science, about the value that their skills can have beyond academia. Beilock has written several pieces on graduate education, which she drew on in writing this column. -APS President Susan Goldin-Meadow What do you see yourself doing after you finish your PhD?” is a question I always ask prospective PhD students during their recruitment visits to the University of Chicago.


  • Teaching Current Directions in Psychological Science

    Aimed at integrating cutting-edge psychological science into the classroom, Teaching Current Directions in Psychological Science offers advice and how-to guidance about teaching a particular area of research or topic in psychological science that has been the focus of an article in the APS journal Current Directions in Psychological Science. Current Directions is a peer-reviewed bimonthly journal featuring reviews by leading experts covering all of scientific psychology and its applications and allowing readers to stay apprised of important developments across subfields beyond their areas of expertise. Its articles are written to be accessible to nonexperts, making them ideally suited for use in the classroom. Visit the column for supplementary components, including classroom activities and demonstrations. Visit David G. Myers at his blog “Talk Psych”.

First Person

  • Tips and Tools for Mentoring Undergraduates as a Graduate Student

    Mentoring undergraduates as a graduate student can be a great experience for everyone involved. Studies show that undergraduates who participate in research tend to learn to “think like a scientist” and have more knowledge about graduate school and interest in science careers than do their peers (Hunter, Laursen, & Seymour, 2007; Russel, Handcock, & McCollough, 2007). Research also suggests that graduate student mentors gain increased teaching, communication, and supervision skills when mentoring undergraduates (Bettencourt, Bol, & Fraser, 1994; Dolan & Johnson, 2009). These skills increase graduate students’ marketability as they transition into the next stage of their career (e.g., faculty position, postdoc, internship). In addition, it can be enjoyable to share your love of the field with a budding psychological scientist.

More From This Issue

  • Why You Should Become a UseR: A Brief Introduction to R

    If you are reading this article, you’ve likely heard of the programming language R but may be avoiding it. R is a programming language for statistical computing and graphics that you can use to clean, analyze, and graph your data. It is widely used by researchers from diverse disciplines to estimate and display results and by teachers of statistics and research methods. It’s free, making it an attractive option, but does rely on programming code — instead of drop down menus or buttons — to get the job done. Programming languages can be intimidating. Maybe you like the comfort and familiarity of whatever statistics program you’ve been working with.

  • Equivalence Testing With TOSTER

    Any science that wants to be taken seriously needs to be able to provide support for the null hypothesis. I often see people switching over from frequentist statistics when effects are significant to the use of Bayes factors to be able to provide support for the null hypothesis. But it is possible to test if there is a lack of an effect using p values. (Why no one ever told me this in the 11 years I worked in science is beyond me). It’s as easy as doing a t test, or, more precisely, as doing two t tests. I’ve created my first R package, TOSTER (as in Two One-Sided Tests for Equivalence in R).

  • YaRrr! The Pirate’s Guide to R

    After teaching several introductory courses on R, I have come to realize that the best way to get people excited about programming is to follow two rules. Rule 1: Make it simple for them to get started. Rule 2: Make it fun. The yarrr R package is designed to follow these rules. One of the main tools in the yarrr package is the pirateplot(). The purpose of the pirateplot was to answer the following question: How can I quickly understand the relationship between one or more categorical independent variables and a continuous dependent variable? This question comes up quite often in experimental research using factorial designs.

  • Finding Bootstrap Confidence Intervals for Effect Sizes With BootES

    BootES (pronounced “booties”) is a free software package for R that computes both unstandardized and standardized effect-size measures for most experimental research designs and finds bootstrap confidence intervals (CIs) for those effect sizes (Gerlanc & Kirby, 2015). We developed bootES to help fill the gap between the data-analysis methods that existing software offers and current recommendations for best practices. Our work follows in the footsteps of a long line of proponents of what has come to be called the “new statistics” (see Geoff Cumming’s article in the 2014 “March Methodology Madness” issue of the Observer). The tools of reform.

  • BayesMed and statcheck

    Many psychological scientists have blamed the field’s replication crisis — which has illuminated the excess of statistically significant findings in the literature — to the fact that most conclusions are based on p values (Wagenmakers, Wetzels, Borsboom, & van der Maas, 2011). Critics say p values are often wrongly interpreted, can’t quantify statistical evidence, and can lead even a null effect to become significant as sample sizes increase (Hoekstra, Finch, Kiers, & Johnson, 2006; Wagenmakers, 2007).

  • Data on Display

    In line with our field’s goals of improving openness, methodological rigor, and reproducibility of science, graphical descriptives (GDs) — the visualization of research data — can be used in the research process and eventually be developed into a routine component of the publication process. GDs can serve as quick and efficient checks for authors, reviewers, and the general scientific audience to assess data distributions, variable relations, outliers, and the appropriateness of statistical analyses while maintaining a level of information privacy and security.

  • Beilock Receives National Academy of Sciences Troland Research Award

    The National Academy of Sciences has announced that APS Fellow Sian L. Beilock is a recipient of the 2017 Troland Research Award. The $75,000 prize is awarded to young investigators in recognition of outstanding scientific achievement within experimental psychology. Beilock, the Stella M. Rowley Professor of Psychology and an Executive Vice Provost at the University of Chicago, primarily conducts research on performance, anxiety, and why people “choke” under pressure. More specifically, her research examines how high-stress situations influence underlying psychological, physical, and neurological mechanisms to compromise performance, even in highly skilled individuals.

  • Learning to Work With R

    Below are some great tutorials that are freely available online and are great introductory tools for getting you started on your journey to R mastery. 1) Getting Started with R The R Website (free) This is the website where you download R. Many of the packages you will want to use are available here.  The RStudio Website (free) This is a great interface that makes R more accessible and user-friendly. However, note that you need to download R before you can download RStudio. 2) Learning the Basics Learning Statistics with R by Danielle Navarro (free) We can’t speak highly enough of this website.

  • Meet Crystal C. Hall, Office of Evaluation Sciences Fellow

    A number of psychological scientists are engaged in the US government’s efforts to improve public programs and policies. The Office of Evaluation Sciences (OES) in the General Services Administration is one of the leaders of this effort.

  • Markus, Schacter, Sternberg to Receive William James Fellow Award at APS Annual Convention

    Hazel R. Markus (Stanford University), Daniel L. Schacter (Harvard University), and Robert J. Sternberg (Cornell University) will receive the APS William James Fellow Award — recognizing their lifetime of intellectual contributions to the basic science of psychology — at the 2017 APS Annual Convention, May 25–28, in Boston. All three will deliver award addresses at the convention. Markus, an APS Fellow, is known for her seminal work examining how people think about the self. Her research has shown how our self-schemas affect our motivations, achievements, and actions.

  • When a ‘Golden Opportunity’ to Bribe Arises, It’s Hard to Pass Up

    The path to corrupt behavior may sometimes be a steep cliff instead of a slippery slope, according to new findings in Psychological Science. In four studies, psychology researchers find that people are more likely to engage in bribery if it occurs as a sudden opportunity rather than as the result of a gradual process. “Unethical behavior like corruption does not always emerge gradually but sometimes occurs abruptly, spontaneously, and unexpectedly,” explains lead researcher Nils C. Köbis of VU Amsterdam, the Netherlands.