Chapter 1    Introduction to Personality Theory17
fei75766_ch01_001-018.indd 17  02/06/20 10:41 AMthatconstruct. Forexample, aninventory purporting tomeasure extraversion should 
notbehighly correlated withsocial desirability, emotional stability, honesty, orself-
esteem. Finally, aninventory hasdiscriminant validity ifitdiscriminates between 
twogroups ofpeople known tobedifferent. Forexample, apersonality inventory 
measuring extraversion should yield higher scores forpeople known tobeextra -
verted thanforpeople known tobeintroverted.
Thesecond typeofvalidity ispredictive validity, ortheextent towhich a
testcanpredict future behavior. Forexample, atestofextraversion haspredictive 
validity ifitcorrelates withfuture behaviors, suchassmoking cigarettes, performing 
wellonscholastic achievement tests, taking risks, oranyother independent criterion. 
Theultimate value ofanymeasuring instrument isthedegree towhich itcanpredict 
future behavior orcondition.
Most oftheearly personality theorists didnotusestandardized assessment 
inventories. Although Freud, Adler, andJung alldeveloped some form ofprojec -
tivetool, none ofthem used atechnique withsufficient precision toestablish 
itsreliability andvalidity. However, thetheories ofFreud, Adler, andJung have 
spawned anumber ofstandardized personality inventories asresearchers and
clinicians have sought tomeasure units ofpersonality proposed bythose theo-
rists. Later personality theorists, especially Hans Eysenck, andtheFive-Factor 
Theorists have developed andused anumber ofpersonality measures andhave 
relied heavily onthem inconstructing their theoretical models. More recently, 
researchers have reported thatsocial media footprints, such asFacebook “likes” 
andshares correlate withandassess personality, sometimes even more accurately 
thanhuman inventory assessments (Azucar, Marengo, &Settanni, 2018; Park 
etal.,2015; Youyou, Kosinski, &Stillwell, 2015).
Key Terms and Concepts
•Theterm“personality” isderived from theLatin word persona, orthemask 
thatpeople present totheoutside world, butpsychologists seepersonality as
much more thanoutward appearances.
•Personality includes allthose relatively permanent traits orcharacteristics 
thatrender some consistency toaperson’s behavior.
•Atheory isasetofrelated assumptions thatallows scientists toformulate 
testable hypotheses.
•Theory should notbeconfused withphilosophy, speculation, hypothesis, or
taxonomy, although itisrelated toeachofthese terms.
•Personality theories cover atleastfivedistinct perspectives: psychodynamic, 
humanistic-positive, dispositional, biological-evolutionary, and learning/
social-cognitive.
•Sixcriteria determine theusefulness ofascientific theory: (1)Does the
theory generate research? (2)Isitfalsifiable? (3)Does itorganize and 
explain  knowledge? (4)Does itsuggest practical solutions to everyday 
problems? (5)Isitinternally consistent? and(6)Isitsimple orparsimonious?Final PDF to printer