1. The Contingent Smile: A Meta-Analysis of Sex Differences in Smiling Marianne LaFrance, Marvin Hecht, & Elizabeth Levy Paluck Presented by: Mandy McCoy

2. Purpose To determine if there are gender differences in smiling To determine if there are gender differences in smiling

3. Literature Review Methods Methods –Electronic Sources (Key words: smile, smiles, and smiling) PsycINFO (1967-2001) PsycINFO (1967-2001) Sociofile (1974-2001) Sociofile (1974-2001) MEDLINE (1975-2001) MEDLINE (1975-2001) ERIC (1966-2001) ERIC (1966-2001) Social Science Citation Index (1973-2001) Social Science Citation Index (1973-2001) Antrhopological Index (1975-2001) Antrhopological Index (1975-2001) Dissertations Abstracts International (1861-2001) Dissertations Abstracts International (1861-2001)

4. –Other abstract references unavailable electronically using the same key words as well as nonverbal communication and facial expression –Reference Lists Literature Review

5. –Conference Programs (through 2000) American Psychological Association American Psychological Association American Psychological Society American Psychological Society Western Psychological Association Western Psychological Association Eastern Psychological Association Eastern Psychological Association Midwestern Psychological Association Midwestern Psychological Association Rocky Mountain Psychological Association Rocky Mountain Psychological Association Society for Personality and Social Psychology Society for Personality and Social Psychology Literature Review

6. –Previous meta-analysis studies –Ancestry Method Reference lists of retrieved studies scanned for additional reports Reference lists of retrieved studies scanned for additional reports –Invisible college method Individual investigators known to have conducted research on facial expression and nonverbal behavior contacted via e-mail Individual investigators known to have conducted research on facial expression and nonverbal behavior contacted via e-mail Literature Review

7. Criteria for Selected Studies Must be a measure of smiling by both sexes Must be a measure of smiling by both sexes –Measure could be smile frequency, smile duration, or ratings of facial pleasantness Studies in which participants were instructed to smile were excluded Studies in which participants were instructed to smile were excluded Studies of children under age 13 were excluded Studies of children under age 13 were excluded

8. Variables 30 variables were coded and measured for reliability 30 variables were coded and measured for reliability Reliability ranged from.71 to 1.00 Reliability ranged from.71 to 1.00

9. Moderators Observation awareness Observation awareness Presence of others Presence of others Engagement with others Engagement with others Instructions to get acquainted Instructions to get acquainted Research setting Research setting Archival material Archival material Familiarity Familiarity Overall constraint Overall constraint

10. Moderators Power Power Caretaking role Caretaking role Teaching Teaching Interview Interview Deception Deception Competition Competition Conflict Conflict Persuasion Persuasion

11. Moderators Social tension Social tension Task tension Task tension Self-disclosure Self-disclosure Embarrassment Embarrassment Sadness Sadness Happiness Happiness Humor Humor

12. Results Total # of participants 109,654 Research reports 162 k418* d.41 95% CI.39-.42 d (including assigned zeros).40 Unweighted mean d.38 Unweighted median d.41 * k = 448 effect size including assigned zeros

13. Regression Coefficients Between Moderators and Smiling Differences Instructions to get acquainted -.006 Competition.002 Sadness.015 Moderator β

14. Regression Coefficients Between Moderators and Smiling Differences Engagement with others -.159*** Research setting -.038* Social tension -.036** * p =.06 ** p <.05 *** p <.01 Moderator β

15. Regression Coefficients Between Moderators and Smiling Differences Observation awareness.163**** Presence of others.258**** Archival material -.160**** Familiarity.146**** Overall constraint -.055**** Power-.132**** Caretaking role.099**** Teaching-.028**** **** p <.001

16. Regression Coefficients Between Moderators and Smiling Differences Interview.134**** Deception-.078**** Conflict-.118**** Persuasion-.060**** Task tension -.055**** Self-disclosure.165**** Embarrassment-.039**** Happiness-.061**** **** p <.001

17. Effect sizes Variation in effect sizes confirmed by a homogeneity analysis Variation in effect sizes confirmed by a homogeneity analysis Q w (417) = 2,072.01, p <.0001 Q w (417) = 2,072.01, p <.0001

18. Conclusions The meta-analysis confirms that women and adolescent girls smile more than men and adolescent boys The meta-analysis confirms that women and adolescent girls smile more than men and adolescent boys Although results were significant, gender differences in smiling depends on a variety of factors Although results were significant, gender differences in smiling depends on a variety of factors