“…In our example, I might hold positive attitudes and feel social pressure towards sustainable means of commuting, yet I might feel that such behavior is too difficult to adopt, this leading to an attitude-behavior gap (Kollmuss & Agyeman, 2002;Lane & Potter, 2007). TPB has been adopted by a number of studies analyzing the determinants of travel mode (Harland, Staats, & Wilke, 1999;Klöckner & Matthies, 2009;Lois, Moriano, & Rondinella, 2015;Noblet, Thøgersen, & Teisl, 2014;Nordfjaern, S ßims ßekoglu, & Rundmo, 2014;Polk, 2003). Further variables have been included to integrate the original framework, as to increase the explanatory power of the model: for instance, we can here mention habits Donald et al, 2014;Verplanken, Aarts, van Knippenberg, & Moonen, 1998), role beliefs , personal norms Parker, Manstead, & Stradling, 1995) and descriptive norms (Donald et al, 2014;Heath & Gifford, 2002).…”