Illusory Correlations  People who have a significant other report higher levels of subjective well-being than people who do not.  Actors who win an academy award live an average of 2-3 years longer than actors who do not receive academy awards.  High school students who are exposed to the arts have higher grades (in all subjects) and SAT scores

Thinking of alternative explanations  In August 2001 the Boston Phoenix ran a story called, ?Queer like your folks.? This article discussed a recent research study which found that daughters of lesbian mothers reported more same-sex experimentation than did daughters of heterosexual mothers. From the headline, it seems that the Phoenix writers interpreted the study to mean that having a lesbian mother caused daughters to engage in same-sex experimentation. However, there is an alternative, non-causal explanation for the finding. What is this?

Thinking of alternative explanations  In August 2001 the Boston Phoenix ran a story called, ?Queer like your folks.? This article discussed a recent research study which found that daughters of lesbian mothers reported more same-sex experimentation than did daughters of heterosexual mothers.

Thinking of alternative explanations  From the headline, it seems that the Phoenix writers interpreted the study to mean that having a lesbian mother caused daughters to engage in same-sex experimentation. However, there is an alternative, non-causal explanation for the finding. What is this?

Should you live together before getting married? (Cosmpolitan Magazine, 1994) For two decades studies have come forward, both in North American and Europe, documenting that:  Couples who live together before getting married were more likely to get divorced than couples who did not live together. Cosmpolitan editors thought this fact should make readers cautious about their living-together decisions.

The National Marriage Project: Top Ten “Myths About Marriage”  (5) Couples who live together before marriage, and are thus able to test how well suited they are for each other, have more satisfying and longer-lasting marriages than couples who do not.  (6) People can’t be expected to stay in a marriage for a lifetime as they did in the past because we live so much longer today.  (7) Marrying puts a woman at greater risk of domestic violence than if she remains single.

Do guns cause crime?

Positive correlation of gun ownership and criminal behavior?  This positive correlation might be mediated by several intervening variables.  Intervening variables can be  *Degree of urbanization: urban versus rural areas  *Culture: Switz, Japanese  *related to culture are variables such as  *education  *media  *Subculture: gangs, hells angles, NRA members, legal gun owners

A study in multiple causality...

When drawing conclusions from data...  Don’t get trapped by “spurious correlations”  Put on your skeptic’s hat, and practice identifying confounding variables, “third variables”

The single factor fallacy  Conclusions can be valid when reasoning at the level of populations but not individuals  Is a generalization falsified when an exception is found?  Beyond billiard-ball cause and effect: How to look for mediating factors

Found a scientifically valid effect?  Now get smart about the strength of the effect

Why is the discipline of developmental psychology more prone to these problems that other disciplines?  dificulting exerting experimental control over variables