Welcome

License

This textbook is an adaptation of Psychology Research Methods: Core Skills and Concepts licensed under a Creative Commons by-nc-sa 3.0 license without attribution as requested by the work’s original creator or licensee.

The following portions of the book were adapted from Introduction to Modern Statistics First Edition by Mine Çetinkaya-Rundel and Johanna Hardin, licensed under a Creative Commons by-sa 3.0 license: Sampling plots; Intro and Anecdotal Evidence portions of Sampling chapter.

This adaptation is authored by Celeste Pilegard (University of California, San Diego) and is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 license.

Cover photo by Photo by Ryoji Iwata on Unsplash. Icons by Eucalyp on Flaticon.

Revisions

Throughout the book: Chapter formatting updated using bookdown package; glossaries restored; references formatted with BibTeX. Photographs refreshed with more recent examples; figures recreated for visual alignment with book design; plots recreated in Base R. Broken links updated or removed. Organization and topic groupings changed by chapter.

  • Developing Research Ideas and Reviewing the Research Literature sections moved from Getting Started chapter to appendix.
  • Qualitative Research section moved from Nonexperiments to Getting Started
  • Sampling chapter created from Survey Research subsection; remaining survey research details moved to Nonexperiments

Appendices: Guidelines on presenting research have been updated to align with the 7th edition of the APA Publication Manual, including citation rules, figure/table formatting examples, and the student/professional paper distinction. The sample APA-style paper has been replaced with an adapted preprint of Pilegard & Mayer (2016) formatted for APA 7. Jitter plots added to data visualization examples. Advice from Bem (2003) deemphasized or removed.

Revisions to portions from Çetinkaya-Rundel & Hardi: Changes in formatting. Stratified random sampling figure adapted to proportionate stratified random sampling.