Phubbing is the practice of ignoring one’s companion or companions in order to pay attention to one’s phone or other mobile device. In the conclusion of a 2017 study published in Personality and Individual Differences, researchers (Wang et al. 2017) concluded “The results indicated that partner phubbing had a negative effect on relationship satisfaction, and relationship satisfaction had a negative effect on depression.” Is this conclusion likely to be the result of an observational study or a controlled experiment? Can we conclude phubbing causes decreased relationship satisfaction from this study? Explain.