 39. Ecological Sampling Methods  817
Ideally, empirical links will emerge between 
automatically sensed situation cues and the 
theorized situational characteristics. Yet the 
overreliance on samples of college-  educated 
young adults bears the risks of capitalizing 
on situations that are unique to some groups 
at the expense of failing to study situations 
that other sociodemographic groups tend to 
encounter. This becomes apparent from low 
frequencies of deceptive, adverse, or mating-  
relevant situations among middle-  aged and 
older adults (Brown & Rauthmann, 2016; 
Rauthmann et al., 2014), but it can be re -
solved by examining diverse samples in di -
verse environments. Still, the mobile device 
revolution has served as a catalyst for real-
world situation research—  regarding both 
objective and subjective information—  as it 
did for real-world behavior research (Hara -
ri, Gosling, Wang, & Campbell, 2015). The 
ethical and legal challenges around sampling 
direct and online conversations, as well as 
pictures from the participant’s point of view, 
are delicate, but solutions are becoming avail -
able, including voice distortion, automatic 
extraction of content to be able to discard the 
raw data, and blurring faces (Robbins, 2017). 
Conceptually, these methods offer powerful 
ways to study real-world person–  situation 
interactions. From a historical perspective, 
they are 21st-  century, high-tech realizations 
of 20th-  century scientific visions (Barker & 
Wright, 1951; Craik, 2000).
Conclusion
Our purpose in this chapter has been to 
provide (1) a rationale for why researchers 
should and (2) a road map for how research -
ers can study personality directly in everyday 
life. In capturing psychological phenomena 
in (nearly) real time, in addressing research 
questions that directly concern everyday life, 
and in studying how personality processes 
unfold within a person, the field is now in -
fusing Craik’s (2000) memorable credo with 
rich empirical reality: “Lives are lived day 
by day, one day at a time, from day to day, 
day after day, day in day out. Lives as we 
experience and observe them are inherently 
quotidian” (Craik, 2000, p. 234).
It is clear, though, that what we are see -
ing now is ultimately only the beginning. Whether or not the field will indeed replace 
the traditional research model with a mobile 
research model by 2025 (Miller, 2012), there 
can be no doubt that research methods for 
studying daily life are here to stay and are 
bound to become more and more powerful, 
user-  friendly, and affordable as our digital 
society continues its path of new, emerging 
mobile technologies and wearables, and the 
Internet of things. As a consequence, it is 
incredibly exciting for the field of personal -
ity psychology that building a deep and rich 
knowledge base of how personality plays out 
in our everyday lives is now no longer a vi -
sion but, rather, a reality well within reach.
NOTE
1. More comprehensive information on these 
methods is provided by Allemand and Mehl, (2017), 
Mehl and Conner (2013), Reis and Gosling (2010), 
and Wrzus and Mehl (2015).
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