Weakness - methodological issues concerning parasocial relationships
most studies on PSR's use self-report methods. these may not reflect the true picture as ppts may want to answer in a way that reflects them in better light and not respond truthfully to the questions.
most research into celebrity worship and PSR's is correlational. E.g. a strong correlation was found between poor body image and intensive celebrity worship in adolescent girls.
this doesn't mean that celeb worship causes poor body image. it may as well be girls wo already have a poor body image tend to engage in a more intensive level of parasocial relationships to enhance their self-esteem.
cause and effect can't be clearly established.
Weakness - problem of social desirability bias. means the reasons for developing parasocial relationships may be different from one uncovered by research, lowering the validity of these explanations, so less applicable IRL.