The Scientific Method

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The Scientific Method

• The Basics
• Read your text

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Scientific Method

• Experimental method generally viewed as best
• Independent variable-changed to test outcome
• Dependent var.-what is measured at the end of the
  experiment
• Should answer why

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Descriptive Studies

• Look at what
• Correlation chief among methods
• Correlation is not causal
• Can say that two variables are related

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Correlational Studies

• Plus side gathers information without altering
  participants experiences
• In the natural world
• Can study things you can not ethically study in
  experiments

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Correlation coefficient

• The closer to 1, the more strongly related the
  variables are
• .73, for example or -.60
• Negatively correlated also can mean strongly
  correlated, it just describes direction
• Ex. exercise more you do, less you weigh

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Some real correlations

• Schizophrenia smoking are positively (and
  highly) correlated
• Tattoos self-esteem are negatively correlated
• Birth order intelligence are negatively
  correlated
• Left-handedness gayness are positively
  correlated

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Significant Results

• Statistical significance-means that the results
  did not occur by chance alone
• Does not mean that the difference was large or
  important
• Practical significance-is it important to every
  day life
• Ex Dumber by the Dozen

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Gender Bias in Research

• Why it exists and what to do about it

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When was the modern scientific method born?

• Roughly in the Victorian era in Europe
• Who was doing research? White, middle-class to
  wealthy males
• So proving women naturally inferior should not be
  a surprise

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Two incorrect assumptions carried over time

• 1. If we find a sex difference in some ability
  or kind of behavior, it means that all males do a
  particular thing and all females do something
  quite different.

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Reality of Sex differences

• Average score for men is different than the
  average score for women
• Sex differences then appear to be more extreme
  and dramatic than they really are

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Look for differences, not similarities

• If you find a difference, there is little
  argument
• If you dont, some will say you didnt test
  enough people
• And perhaps most importantly, you wont get
  published

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2nd incorrect assumption

• 2. that sex differences are biologically based
  and, therefore, inevitable and unchangeable.

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Females barred from Boston Marathon

• In 1963, women first allowed to run it
• Time 1 hour and 20 min slower than the mans
  record
• 1983, Joan Benoit won in 2 hours/22 min/43
  seconds
• Or 15 minutes slower than the male winner

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Other ex of mutable biology

• Menstruation-no surprise to anyone ages at start
  are changing
• Age at onset earlier, age at cessation later in
  U.S. Europe
• Nutrition exercise affect it, particularly Body
  fat

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!Kung women are quite different

• Start menstruation at about age 18
• Nurse children, so menstruation does not soon
  return for them (does for U.S. women due to
  nursing technique)
• Menstruation rare event
• With no contraception, have only 4-5 children
• Enter menopause in late 30s/40

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In our culture cognitive differences thought to
be biological

• are showing rapid changes
• E.g. 1947-1983 Differential Aptitude Test (DAT)
• gender differences in subtests changed
• declined significantly disappeared in some
  cases

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Other sources of Bias

• When differences are expected, then found, the
  research is rarely questioned
• gtgtwomen are not as smart as men
• proof womens heads are smaller
• thus, their brains are smaller
• proved by Romanes, 1887

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Ws lesser intelligence was then

• Considered a survival benefit for the species
• Women had no intellectual interests to distract
  them from taking care of children

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People tend to believe research

• If it confirms something they want to believe
• If the res is later discredited, most fail to
  hear about it
• Incorrect facts thus have a life of their own
• So how many of you believe eggs are a major
  source of cholesterol?

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Choosing a Problem

• Societal values influence choice of topic
• school achievement a major one in U.S. and of
  little concern outside the industrialized world
• Gender ex heart disease well funded, as are most
  male diseases. Until recently, breast cancer
  wasnt.

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Then

• Selecting variables
• Choosing a design
• Formulating a hypothesis (posit differences)
• Collecting data-may define it in such a way that
  measurement will only provide one answer

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And

• Analyzing results-allowing personal values to
  guide the choice of which factors to evaluate
• Interpreting results-making gender differences
  seem large when they are not
• More importantly, making differences seem
  biological when no bio data collected

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Example of Bias in Research

• Particularly the Media reports of it

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Benbow Stanley 1986

• Males greater proficiency in math
• Compared 7th graders scores on SAT
• Males scored higher
• Claim hormonal differences lead to males
  greater proficiency
• thus, biological innate
• No hormonal measure in study

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Media Reaction

• Are Boys Better at Math? (NY Times, 12-07-80).
• Do Males have a Math Gene? (Newsweek, 12-15-80)
• The Gender Factor in Math A New Study Says Males
  May Be Naturally Abler than Females (Time,
  12-15-80).

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Publication bias again

• Publication of findings showing differences, none
  showing lack of differences

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Probably even worse when we study deviance

• Studies of gays/lesbians tend to show how bad
  life will be
• Trauma of Gay life is what is published
  (newspapers journals)
• Youth get expectation of poor outcomes
• See article In the Family, Sp 01 by Russell
  Bohan

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What can we do to reduce bias?

• In addition to whats in the book
• Demand more from research
• Be a good consumer of research

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Vampires revisted (1991)

• LeVay (1991) brain differences in
• heteros/homosexuals after death
• Examined 19 brains of homosexual men
• Examined 16 brains of men he presumed were hetero
• Examined 6 brains of women he presumed were hetero

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LaVay continued

• All of the homosexual men
• 1 of the women
• 6 of the presumed hetero men
• had died of causes related to AIDs
• Known to cause brain tissue change

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And concluded

• That hetero/homosexual men had different
  hypothalmi
• Published in Science, a respected journal
• See any problems?