Which of the following statements are correct?

1.Pearson's r is an appropriate effect size to describe the relationship between two continuous variables 2.Cohen's d is an appropriate effect size to describe the magnitude of mean differences among three or more groups 3.Effect sizes provide important information regarding the magnitude of the effects.

a-(1) and (2) only

b-(1) and (3) only

c-(1), (2), and (3)

d-(2) and (3) only

"Jennifer hypothesizes that age and annual income predict Californian's choices to move to a different state on a 5-pint Likert-type scale (1 strongly disagree, 5 strongly agree)." Which of the following statistical tests is appropriate to test this hypothesis?

a-Pearson's correlation

b-Independent-samples t-test

c-Simple linear regression

d-One-way ANOVA

Lily wants to know if room temperature and gender predict aggression (scale of 1 - 9). One hundred participants are randomly assigned (50 female, 50 male) to either a hot or cold room and then they complete the aggression questionnaire. Which of the following can NOT threaten the internal validity of this experiment?

a-Lack of multiple operationalization

b-Selection bias

c-Mortality

d-Maturation