As part of an “internet cat videos/photos” study, Dr. Jessica Gall Myrick posted an on-line survey to Facebook and Twitter asking a series of questions regarding how individuals felt before and after the last time they watched a cat video on the Internet. One of the goals of the study was to determine how watching cat videos affects an individual’s energy and emotional state. People were asked to share the link, and everyone who clicked the link and completed the survey was included in the sample. More than 6000 individuals completed the survey, and the study found that after watching a cat video people generally reported more energy, fewer negative emotions, and more positive emotions.

(a) Would this be considered a simple random sample from a target population? Why or why not? 

(b) Ignoring sampling bias, what other ways could bias have been introduced into this study?