“…Intra-individual variability in affect can be studied by attending to the within-person variance in PA and NA sum scores across visits. There is growing interest in intra-individual variability in affective symptoms amongst smokers making quit attempts (e.g., Geiser, Griffin & Shiffman, 2016) arising from findings that such variability is substantial (Dziak et al, 2015; McCarthy et al, 2006), and that it may significantly influence the success of quit attempts (Piasecki et al, 2003a, b). Thus, in addition to the effects of mean affect, greater intra-individual variability in affect that emerges in the post-quit period is anticipated to increase the likelihood of relapse to smoking (see e.g., Hedeker, Mermelstein, Berbaum, & Campbell, 2009; McCarthy et al, 2006; Piasecki et al, 2003a, b).…”