Difference amongst differences. Sex-differences in height have been compared to the sex-difference in aggression several times in lecture and readings. Height is a metric and aggression uses behavioral observations/reports. The next several slides clarify how differences in means are normalized based on population’s standard deviation from means in order to determine effect size. Effect sizes can then be compared between measures.
Need to examine variation of height
Need to examine variation of height
So, how can we measure variation within the groups?
Consider a population consisting of the following eight values:These eight data points have the mean (average) of 5:To calculate the population standard deviation, first compute the difference of each data point from the mean, and square the result of each:Next, compute the average of these values, and take the square root:This quantity is the population standard deviation; it is equal to the square root of the varianceWhen comparing two groups with differed SD’s, standard deviation is the “pooled” (average) standard deviation across the two groups
Graphical comparison of distribution
Where is the effect of sex larger—graph 1 or 2?
Why is your point of view relevant?
Announcements:Miss RepresentationMovie Night on Thursday Jan 31st at 7pmPaper#1 due Feb. 7th
1.Sexual Harassment2.Sex and Sports3.Effect size + statistical significance4.Writing Tips
Abigail SaguySex and Harassment Lecture 1/23/13Main point: Conceptions of and laws against sexualharassment depend on specific historic and culturalcontexts. By framing sexual harassment asdiscriminatory, violence, or bad business practice willlead to different consequences.
Why did Dr. Saguy compare USA and France?-Major industrialized democracies-Mission to advance universal concepts of justice and human rights-Similar rates of females employment-Sexual harassment is a problemWhat methods did Dr. Saguy use to determine What is SexualHarassment?-Interviews-News media-Legal research
Sexual Harassment (Top 5 from www.NewsOne.com)5. Bill O’ReillyBill O’Reilly was charged with sexual harassment and sued for $60 millionin 2004 by former producer for The O’Reilly Factor Andrea Mackris.Mackris would claim that O’Reilly would sexually harass her and makecrude comments about masturbation, threesomes, and Caribbean showerfantasies.She would later settle out of court for an undisclosed amount of money.
Sexual Harassment (Top 5 from www.NewsOne.com)4. Bill ClintonWhile Bill Clinton was running for president in 1991, Paula Jones, a formerArkansas state employee claimed that Clinton pulled down his pants andasked her for oral sex in a hotel room.Clinton would wind up paying Jones just under one million dollars, despitenever admitting guilt just to keep her quiet.
Sexual Harassment (Top 5 from www.NewsOne.com)3. Mark FoleyMark Foley was a Republican congressman from Florida who was also thechairman of the House Caucus on Missing and Exploited Children.Foley became infamous as the first politician caught up in the Internet eraof sexual harassment scandals. He was caught sending emails to malecongressional pages asking for fellatio and pictures of their penises. Hewould also send sexually explicit instant messages to young males.Foley would later enter rehab and claim that he was molested himself.
Sexual Harassment (Top 5 from www.NewsOne.com)2. Britney SpearsBritney Spears was sued by former bodyguard Fernando Flores for sexualharassment.Flores would claim that Spears made unwanted sexual advances to him,exposed her private parts to him on numerous occasions, and said thatshe would abuse her children numerous times.Spears’ attorney accused the bodyguard of “trying to cash in on Ms.Spears’ celebrity by making salacious claims of misconduct.”
Sexual Harassment (Top 5 from www.NewsOne.com)1. Clarence ThomasWhen Clarence Thomas was nominated to the Supreme Court by formerpresident George H.W. Bush, old allegations of sexual harassment werelevied upon him from an attorney who worked for him at the DepartmentOf Education. The woman’s name was Anita Hill.Hill was called to Senate to testify and said that Thomas made commentsabout group sex, rape, bestiality, and bragged about his anatomy andsexual prowess to her. She also said he once asked, “Who put a pubic hairon my Coke?”Thomas was later confirmed despite Hill’s testimony.
Clarence Thomas + Anita Hill: Sexual Harassment TrialPBS:http://www.youtube.com/watch?feature=player_embedded&v=1lEEDD2vxaE#!Sex and Justice:http:://www.anitahill20.org/We still believe Anita Hill:http://www.youtube.com/watch?v=w3_4hp_XYxIDaily Show: Women in Combathttp://www.thedailyshow.com/watch/mon-january-28-2013/women-s-war-daily---military-brohesion
How is sexual harassment represented in themedia? In what ways does the mediadownplay the seriousness of sexualharassment? In what ways does the mediarepresent is as serious?
Saguy argues that the American mass media iscontrolled by business and dependent onadvertisement revienues and are under pressure towrite stories that “sell” (Introduction, 11).Why are sexual harassment scandals such a hotcommodity? Can you think of any particularlyegregious examples, either from the text or fromyour own experiences of watching the news?
Saguy suggests that both the French and theAmerican feminists who worked to publicize anddiscourage the practice of sexual harassment in lawand practice were limited by their “distinct political,legal, and cultural, constraints and resources.”What factors influenced these differing terrains?
What are the three “frames” for regulating sexualharassment articulated by Saguy? How did each comeabout? What are the advantages of each? What are thedisadvantages?For example, Saguy suggests that American lawconceptualizes sexual harassment as “group-based”disadvantage and French law as a form of “interpersonalviolence” what are the broad ramifications of each? Howhave corporations been influenced by law and nationalcultural context?
Saguy argues:“The formulation of sexual harassment as aconcept and a body of law at all, as well as the particular way itis conceptualized, has important implications for genderequality, for expectations and behaviors linked to sexuality, andfor what sort of social interactions are considered appropriateor desirable in the workplace in particular and in other publicand private spheres more generally.” (Introduction, 4).According to each frame, what behaviors are consideredappropriate or desirable in the workplace? Which types ofbehaviors are considered inappropriate? Which are consideredinappropriate yet tolerated?
How has American sexual harassment law enabledwomen to come forward with complaints of sexualharassment? What barriers persist?
Women’s Sexual Harassment of Men:The law proscribes gender-based sexual harassment, are men subject tosexual harassment? How is it similar and how is it different?How do gender roles influence men’s ability to “speak out” against sexualharassment?Does women’s lack of institutional power (gender-based occupationalsegregation, “the glass ceiling,” “the glass elevator”) influence the powerlandscapes that color sexual harassment practices and policies?How do we understand gender equality as it pertains to the rights of mento be free from sexual harassment?
Eric VillaineAthletes’ Bodies, Sexed Bodies 1/29/13Main point: From the beginning of the 20th century totoday, sex testing has been a controversial aspect forelite female athletes. However, DSDs athletes don’thave a competitive advantage compared to athleteswith favorable genetics.
Starting with Dr. Villain’s FINAL THOUGHTS- Sports rules are arbitrary- No competitive advantage between DSD athletes and athletes with favorable genetics- Gender challenges are undesirable- Biological parameters of sex are imperfect- PrivacyWhich if any of these points are you going to address in yourIOC paper? How and why?
What are the 3 relevant DSDs when consideringandrogen advantage in sports?Are transgender people allowed to participate in eliteathletics?What are 3 pieces of evidence that support the idea thatintersexuality provides an athletic advantage?
M. Haselton REVIEW (what she wants you to know)Evolutionary Record:Decreasing sexual dimorphism in human lineagePersistent asymmetries:Size, parental investment, aggressionEffect Size….
Are men’s heights different from women’s heights? Women’s mean Men’s mean = women = menNumber of People 52” 54” 56” 58” 60” 62” 64” 66” 68” 70” 72” 74” 76” 78” 80” Height Graph 2
Statistical significance: the probability of havingobserved as large of a difference as the one youobserved if only chance were at work.If the chances of observing a difference by chance alone is lessthan 5% (denoted as p < 0.05), then we can conclude thatprobably more than just chance was at work . Depends onsample size.
Are men’s heights different from women’s heights? How big is this effect? Women’s mean Men’s mean = women = menNumber of People 52” 54” 56” 58” 60” 62” 64” 66” 68” 70” 72” 74” 76” 78” 80” Height Graph 2
Histogram: illustrates population distributionsNumber of People = 1 man 52” 54” 56” 58” 60” 62” 64” 66” 68” 70” 72” 74” 76” 78” 80” Height
Histogram: illustrates population distributionsNumber of People = 1 man = men 52” 54” 56” 58” 60” 62” 64” 66” 68” 70” 72” 74” 76” 78” 80” Height
Histogram: illustrates population distributions = 1 woman = womenNumber of People = 1 man = men 52” 54” 56” 58” 60” 62” 64” 66” 68” 70” 72” 74” 76” 78” 80” Height
How big the effect of sex is on height depends on height variation within sexes. = women = menNumber of People 52” 54” 56” 58” 60” 62” 64” 66” 68” 70” 72” 74” 76” 78” 80” Height
Measure of variation….• Standard deviation (SD): = average amount by which an individual is different from his or her group mean• sometimes written as σ (pronounced “sigma”)
Computing Standard DeviationPopulationMean (average)(Difference of each point from mean)^2Square-root(variance)
Mean + SD• “Normal distribution”/bell-shaped curve: standard deviation tell us what percentage of people will be at a certain level of a trait• E.g., if women’s mean height is 63” and σ = 3” Then we can assume that about 68% of women will be within one standard deviation above or below the mean (i.e. between 60-66”)
Effect size• Effect size: the degree of non-overlap between two groups’ distributions on some variable (e.g., a trait like height) Effect size (d) = MeanGroup1 – MeanGroup2 σ• Unlike a difference between means, an effect size takes into account the amount of variation within each group
Graph 1 Women’s mean Men’s mean = women = menNumber of People 52” 54” 56” 58” 60” 62” 64” 66” 68” 70” 72” 74” 76” 78” 80” Height
Graph 2 Women’s mean Men’s mean = women = menNumber of People 52” 54” 56” 58” 60” 62” 64” 66” 68” 70” 72” 74” 76” 78” 80” Height
Graph 1+2 Women’s mean Men’s mean = women = menNumber of People 52” 54” 56” 58” 60” 62” 64” 66” 68” 70” 72” 74” 76” 78” 80” Height
Where is the effect of sex larger— graph 1 or 2?• The difference in means is exactly the same• Variation within each group’s distribution differs— and, therefore, the amount of distribution’s non- overlap• Effect of sex is MUCH larger in graph 2, but we would never know if all we looked at were the means!
Effect size• Less overlap Larger effect size• More overlap Smaller effect size• All else equal, HOW does increasing the difference between means change effect size?• All else equal, how does increasing the variation within groups change effect size?
Effect size (d) Percent Non-overlap% of non-overlap for effect 0.0 0% sizes ranging from 0.0 to 2.0 0.1 0.2 7.7% 14.7% 0.3 21.3% 0.4 27.4% 0.5 33.0% 0.6 38.2% 0.7 43.0% 0.8 47.4% Most psychological sex- 0.9 51.6% differences d < 1.0 1.0 55.4% But even when d = 1.0 1.1 58.9% 44.6% of men’s and women’s 1.2 62.2% distributions overlap 1.3 65.3% Take-home: even when a sex- 1.4 68.1% difference is present, women 1.5 70.7% and men are very similar—often 1.6 73.1% much more similar than they 1.7 75.4% are different. 1.8 77.4% 1.9 79.4% 2.0 81.1%
Effect size vs. statistical significance• Larger difference is more likely to be statistically significant.• BUT statistical significance also depends on sample size (how many people you collected data from).• In a large sample of participants, a very small difference will often be statistically significant.• In a small sample of participants, a very large difference will often be statistically non-significant.
• In psychology, effect sizes are interpreted as follows: 0.2 = a small effect (15% non-overlap) 0.5 = a medium effect (33% non-overlap) 0.8+ = a large effect (47% non-overlap)
Writing an Opinion EssayRhetoric – The Art of PersuasionEthos: writer’s voice (must be informed).Logos: logical content of the argument andlogical conclusions.Pathos: anticipated emotional reaction ofaudience to content.
The Opinion Essay• The topic is subject to controversy• Expresses a compelling opinion that cannot necessarily be proven to be true• Purpose: to convince our reader that our point of view is correct.• Presents author’s point of view supported by reasons and examples.• The opposing viewpoint is also suggested, it goes with arguments that show that it is unconvincing.
You May Use the Following Expressions to Give Your Opinion• As far as I am concerned, …• I am (not) convinced that …• In my opinion/view …• My opinion is that …• I (firmly)believe …• I (definitely) feel/think that …• I am inclined to believe that …• I was interested/surprised/shocked to find out that…• As I see it…• It seems to me…
Opinion Essay• Introductory paragraph with thesis – Introduce the topic, the controversy – Your clear opinion IS the thesis statement• Body with supporting arguments – Give reasoned arguments to support your opinion. – Each argument forms a separate paragraph. – Add details, facts and examples to support your arguments – Present opposing view-points and refute• Conclusion – The main points of the essay are summarized and the author’s opinion is restated in other words. – May offer a solution or provides a warning of what will happen if your advice is not heeded