ADVANCED PLACEMENT PSYCHOLOGY

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ADVANCED PLACEMENT PSYCHOLOGY

• Thinking Critically with Psychological Science
• http//psychtutor.weebly.com/research-methods.html

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Objective ONE

• Describe hindsight bias, and explain how it can
  make research findings seem like mere common sense

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THREE LEVELS OF HINDSIGHT BIAS

• I-knew-it-all-along phenomenon!
• It involves the tendency people have to assume
  that they knew the outcome of an event after the
  outcome has already been determined
• There are three levels of hindsight bias that
  stack on top of each other, from basic memory
  processes up to higher-level inference and
  belief

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THREE LEVELS OF HINDSIGHT BIAS

• I-knew-it-all-along phenomenon!
• The first level of hindsight bias, memory
  distortion, involves misremembering an earlier
  opinion or judgment ('I said it would happen')
• The second level, inevitability, centers on our
  belief that the event was inevitable ('It had to
  happen')
• And the third level, foreseeability, involves the
  belief that we personally could have foreseen the
  event ('I knew it would happen')

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Limits of Intuition and Common Sense/EXAMPLE 1

• I-knew-it-all-along phenomenon!
• On the evening of an important NBA game by the
  Orlando Magic, your friend predicts that the
  Magic are going to win by a large margin. In
  fact, the Magicdo end up winning the game,
  causing your friend to boast I predicted it!

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Limits of Intuition and Common Sense/EXAMPLE 2

• I-knew-it-all-along phenomenon!
• A letter comes in the mail informing an
  individual that she was accepted into a college.
  When she tells her mother she says, I really had
  a feeling that you were going to get in (even
  though she had expressed doubts to her husband
  earlier that week).

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Limits of Intuition and Common Sense/EXAMPLE 3

• I-knew-it-all-along phenomenon!
• You are nervous to take an exam for which you
  waited to study until the very last minute. When
  you take the exam, you feel unsure about the
  results however, when your grade comes back a
  B, you exclaim to your friends, I was sure that
  Id aced that exam! and actually believe it in
  hindsight.

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Limits of Intuition and Common

• Hindsight bias can also make us overconfident in
  how certain we are about our own judgments.
• Research has shown, for example, that
  overconfident PEOPLE are more likely to take on
  risky, ill-informed situations that fail to
  produce a significant consequence or result

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Objective TWO

• Describe how overconfidence contaminates our
  everyday judgments

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Overconfidence Effect

• Johann Sebastian Bach, was anything but a one-hit
  wonder.
• He composed numerous works.
• How many concertos do you think Bach composed?
• Choose a range, for example, between one hundred
  and five hundred, so that your estimate is at
  least 98 percent correct and only 2 percent off.
• Write it on a piece of paper before you read on.

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Overconfidence Effect

• Please do the same with these two questions
• How many member states does OPEC (Organization of
  the Petroleum Exporting Countries) have?
• How long is the Nile river?

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Overconfidence Effect

• Johann Sebastian Bach composed 1,127 works that
  survived to this day. He may have composed
  considerably more, but they are lost.
• OPEC has 12 member states.
• The Nile river is 4132 miles long.

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DEMONSTRATION

• HANDOUT 2-8
• FEMALE EMOTIONALITY
• Look at the HANDOUT and at the bottom select the
  BEST CHOICE

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DEMONSTRATION
WERE THE PARTICIPANTS EMOTIONAL?
YES NO
YES
NO
WERE THE PARTICPANTS WOMEN
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DEMONSTRATION

• An illusory correlation is the perception of a
  relationship between two variables when only a
  minor or absolutely no relationship actually
  exists
• Stereotypes are a good example of illusory
  correlations.
• Research has shown that people tend to assume
  that certain groups and traits occur together and
  frequently overestimate the strength of the
  association between the two variables

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Limits of Intuition and Common Sense

• Overconfidence
• Robert Vallorie study (1990)
• The overconfidence effect is a well-established
  bias in which someone's subjective confidence in
  their judgments is reliably greater than their
  objective accuracy, especially when confidence is
  relatively high.
• For example, in our last quiz, students overall
  rated themselves wrong _?_ of the time

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Limits of Intuition and Common Sense

• Overconfidence
• Robert Vallorie study (1990)
• The overconfidence effect is a well-established
  bias in which someone's subjective confidence in
  their judgments is reliably greater than their
  objective accuracy, especially when confidence is
  relatively high.
• For example, in our last quiz, students overall
  rated themselves wrong _40_ of the time (it is
  the national average on these studies.

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Scientific Approach

• Two phenomena hindsight bias and
  overconfidence illustrate why we cannot rely
  solely on intuition and common sense
• Scientific attitude, fed
  by curious skepticism
  and by
  humility, can help
  us sift reality from
  illusions

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Objective THREE

• Explain how the scientific attitude encourages
  critical thinking

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The Scientific Attitude

• As scientists, psychologists approach the world
  of behavior with a curious skepticism
• Polish proverb to believe with certainty we
  must begin by doubting.
• Psychologists ask two
  questions
• What do you mean?
• How do you know?

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Smart Thinking

• The scientific attitude prepare psychologists and
  other professionals to think smarter.
• Smart thinking, called critical thinking,
  examines assumptions, discerns hidden values,
  evaluates evidence, and assess conclusions
• At what (approx) age does it begin?
• At what (approx) age do we assign as having it
  (Frontal Lobe)?

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Smart Thinking

• Questioning attitude regarding psychologists
  assumptions and hidden values is known as
  critical thinking another way of saying this

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Smart Thinking

• When you question whether anecdotal evidence can
  be generalized to all people, you are applying
  critical thinking

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Objective FOUR

• Describe how psychological theories guide
  scientific research

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Experimental Research

• Builds on the principles of positivist
  perspective and natural sciences
• (1) Starts with a causal hypothesis
• (2) Modify one specific aspect of a situation
  that is closely connected to the cause, and
• (3) Compare the outcome to what existed without
  the modification

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Wilhelm Wundt

• Credited with setting up the
  first psychology laboratory
• Leipzig, Germany
• 1879
• He claimed the psychological experience is
  composed of compounds, much like in chemistry
• He claims he found two other compounds
  sensations and feelings

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Wilhelm Wundt

• Methods proved cumbersome and unreliable
• BUT
• Wundts work is unimportant,
  however his procedure ultimately led to what he
  and his student (Edmund Titchener) will call
  introspection which will result in the
  SCIENTIFIC METHOD

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Scientific Method
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Steps in Experiment (1)

• Hypothesis
• Choose a design
• Design experiment
• How to introduce IV
• How to measure DV
• Locate subjects
• Randomly assign subjects

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Steps in Experiment (2)

• Gather pretest data
• Run experiment
• Introduce treatment
• Measure DV
• Gather posttest data
• Debrief
• Analyze data

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MARSHMALLOW EXPERIMENT

• The "marshmallow experiment" is a well known test
  of this concept conducted by Walther Mischel at
  Stanford University
• In the 1960s, a group of four-year-olds were
  given one marshmallow and promised a second one
  on the condition that they wait twenty minutes
  before eating the first one.
• Some children were able to wait and others could
  not.

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EXPERIMENT

• Deferred gratification or delayed gratification
  is the ability to wait in order to obtain
  something that one wants

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EXPERIMENT

• Definition
• One type of research method in which the
  investigator manipulates one or more independent
  variables (IV)
• to determine the effect(s) on some behavior (the
  dependent variable) while controlling other
  relevant factors

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EXPERIMENT

• Dependent Variable
• The variable in an experiment that is measured
  the outcome of an experiment.
• ?????
• Being able to delay gratification or not
• Independent Variable
• The variable in an experiment that is manipulated
  or compared
• ?????
• The MARSHMALLOW

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THE EXPERIMENT

• Functional Magnetic Resonance Imaging.
• When presented with tempting stimuli, individuals
  with low self-control showed brain patterns that
  differed from those with high self-control.
• The researchers found that the prefrontal cortex
  (a region that controls executive functions, such
  as making choices) was more active in subjects
  with higher self-control
• The ventral striatum (a region thought to process
  desires and rewards) showed boosted activity in
  those with lower self-control.

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EXPERIMENT

• Deferred gratification or delayed gratification
  is the ability to wait in order to obtain
  something that one wants

• Kate Dawson argued that people with poor impulse
  control suffer from "weak ego boundaries".
• This term originates in Psychoanalytic theory of
  personality where the id is the pleasure
  principle, the ego is the reality principle, and
  the superego is the morality principle.

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EXPERIMENT

• Deferred gratification or delayed gratification
  is the ability to wait in order to obtain
  something that one wants

• Cognitive-behaviorists believe that poor impulse
  control may be related to biological factors in
  the brain.
• Researchers have found that children with FETAL
  ALCOHOL SYNDROME are less able to delay
  gratification

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MARSHMALLOW EXPERIMENT

• The researchers then followed the progress of
  each child into adolescence and demonstrated that
  those with the ability to wait were
• better adjusted and more dependable (determined
  via surveys of their parents and teachers),
• (2) scored significantly higher (avg. 210 pts)
  on the Scholastic Aptitude Test and
• (3) predictive of delinquency due to poor impulse
  control as a child

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Psychologists can test the hypotheses and refine
the theories using 1. Description 2.
Correlation 3. Experimental Methods
Scientific Method
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Objective FIVE

• Identify an advantage and a disadvantage of using
  case studies to study behavior

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Description

• The starting point of any science is description
• We observe and draw conclusions everyday
• Psychologists observe and draw conclusions like
  every one of us except they are more objective
  and the process more systematic
• Among the oldest research method is the case study

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CASE STUDY

• A case study is an in-depth exploration of a
  particular context, such as a classroom or group
  of individuals that involves the collection of
  extensive qualitative data usually via interview,
  observation, and document analysis.

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Description

• Case Studies
• Advantages
• Suggest hypotheses for further study
• Show us what can happen
• Disadvantages
• Individual cases can be misleading as a person
  may be atypical
• Unrepresented information can lead to mistaken
  judgments and false conclusions

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Objective SIX

• Identify the advantages and disadvantages of
  using surveys to study behavior and mental
  processes, and explain the importance of wording
  effects and random sampling

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Survey

• The survey method looks at many cases in less
  depth
• Harris and Gallup polls
• However, asking questions can be tricky, and the
  answers may well depend on your wording and your
  choice of respondents

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QUESTION
LETS DO A SURVEY, OKAY?
WHO IN THIS CLASSROOM CHEATS ON MY STUFF?
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Survey Wording Effects

• Even subtle changes in the order or wording of
  questions can have major effects on the responses
• Surveys indicate that people are much less likely
  to support welfare than aid to the needy
  indicating changing the wording can change the
  result of the survey
• Audience selection is critical
• School Survey Do you cheat on tests

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Survey Random Sampling

• Everyday we spend a lot of time with a biased
  sample of people mostly those who share our
  attitudes and habits
• When we wonder how many people hold a particular
  belief, those who think as we do come to our mind
  first
• This tendency to overestimate others agreement
  with us is the false consensus effect
• Liberals think more people support liberal views
  and vice-versa with conservatives

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Random Sampling

• You can easily describe human experience using
  your estimates of others, and supplement it with
  anecdotes and personal experiences, but for an
  accurate picture of the whole population.you
  must use a representative sample

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Random Sampling

• If you wish to survey students at West Shore, how
  could you survey a representative sample of the
  total population the who group you want to
  study and describe?

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Random Sampling

• If you wish to survey students at West Shore, how
  could you survey a representative sample of the
  total population (all the cases in a group) the
  whole group you want to study and describe?
• You would choose a random sample, one in which
  every person in the entire group has an equal
  chance of participating

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Random Sampling

• How would you conduct a random sample?
• Send a survey to 100 of the students?
• Oruse a table of random numbers to pick
  participants from a student listing and then
  making sure you involve as many as possible
• Oruse a random numbers generator

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Random Sampling

• Let us assume you had a school with a 1000
  students, divided equally into boys and girls,
  and you wanted to select 100 of them for further
  study. You might put all their names in a drum
  and then pull 100 names out. Not only does each
  person have an equal chance of being selected, we
  can also easily calculate the probability of a
  given person being chosen, since we know the
  sample size (n) and the population (N) and it
  becomes a simple matter of division n/N x 100
  or 100/1000 x 100 10
• Many statistics books (statistical computer
  programs) include a table of random numbers,
  which are predetermined sets of random numbers
• For instance, if the students in our school had
  numbers attached to their names ranging from 0001
  to 1000, and we chose a random starting point,
  e.g. 533, and then pick every 10th name
  thereafter to give us our sample of 100 (starting
  over with 0003 after reaching 0993).

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Objective SEVEN

• Identify an advantage and a disadvantage of using
  naturalistic observation to study behavior

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Naturalistic Observation

• Defined as observing and recording behavior in
  naturally occurring situation without trying to
  manipulate and control the situation
• Like surveys and case studies, naturalistic
  observations do not explain behavior, but merely
  describes it
• Jane Goodalls (1998) studies with chimpanzees

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Naturalistic Observation

• Naturalistic Observations can be conducted with
  humans
• Example
• In order to compare the pace of life in different
  countries, investigators measured the speed with
  which postal clerks completed a simple request

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Naturalistic Observation

• Advantage
• Provides researchers an opportunity to watch and
  record behavior in naturally occurring situations
• Disadvantage
• Like surveys and case studies it does not
  explain behavior, but merely describes it

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INTRODUCTION TO PSYCHOLOGY

• Why Study Psychology?

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DEMONSTRATION
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Objective FOURTEEN

• Explain the difference between an independent and
  a dependent variable

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Independent and Dependent Variables

• Viagra experiment (1998)
• 69 of Viagra-assisted attempts at intercourse
  were successful, compared to 22 for men
  receiving the placebo
• The experiment manipulated one drug factor which
  is called the independent variable
• The dependent variable (outcome factor) may
  change in response to manipulations of the
  independent variable

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Independent and Dependent Variables

• An INDEPENDENT VARIABLE is a variable that is
  manipulated, measured, or selected by the
  researcher as an antecedent condition to an
  observed behavior. In a hypothesized
  cause-and-effect relationship, the independent
  variable is the cause and the dependent variable
  is the outcome or effect.

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Independent and Dependent Variables

• A DEPENDENT VARIABLE is a variable that is not
  under the experimenter's control -- the data. It
  is the variable that is observed and measured in
  response to the independent variable.

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Independent and Dependent Variables

• A variable is anything that can vary
• Experiments aim to manipulate an independent
  variable, measure the dependent variable, and
  control all other variables
• An experiment has at least two different
  conditions an experimental condition and a
  comparison or control condition

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Objective EIGHT

• Describe positive and negative correlations, and
  explain how correlational measures can aid the
  process of prediction

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Correlation

• Correlation research is most useful for purposes
  of prediction
• Surveys and Naturalistic Observations
• When one or more traits or behavior accompanies
  another, we
  say they correlate

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Correlation

• Correlation coefficient
• Is a statistical measure of a relationship
• It reveals how closely two things vary together
  and how well either one predicts the other
• Example Know how much aptitude test scores
  correlate with school success tells us how well
  the scores predict school success

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Correlation

• Scatterplot
• A graph cluster of dots, each of which represents
  the values of two variables.
• The slope of the points suggests the direction of
  the relationship between the two variables
• The amount of scatter suggests the strength of
  the correlations (little scatter indicates high
  correlation)

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Correlation

• A correlation being negative has nothing to do
  with its strength or weakness, but just means the
  two things relate inversely
• Example
• As toothbrushing goes up from zero, tooth decay
  goes down
• Brushing and decay correlate negatively
• A weak correlation, indicating little or no
  relationship, has a coefficient near zero

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Correlation

• The more TV is on in the homes of young children,
  the less time they spend reading
• Positive or negative?

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Correlation

• The more TV is on in the homes of young children,
  the less time they spend reading
• negative

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Correlation

• The more sexual content teens see on TV, the more
  likely they are to have sex.
• Positive or negative?

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Correlation

• The more sexual content teens see on TV, the more
  likely they are to have sex.
• Positive or negative?
• Positive

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Correlation
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Correlation
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Correlation
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Objective NINE

• Explain why correlational research fails to
  provide evidence of cause-effect relationships

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Correlation and Causation

• Correlations help us predict and they restrain
  the illusions of our flawed intuition
• Example
• Watching violence correlates with (and therefore
  predicts) aggression
• Does it mean it causes aggression?

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Objective TEN

• Describe how people form illusory correlations

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Illusory Correlations

• Illusory correlations are beliefs that
  inaccurately suppose a relationship between a
  certain type of action and an effect.
• When we believe there is a relationship between
  two things, we are likely to notice and recall
  instances that confirm our belief

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Illusory Correlations

• Illusory thinking helps explain why people
  believe (and many still do) that
• Sugar made children hyperactive
• Getting cold and wet caused one to catch a cold
• When the weather changes it causes arthritis
  pain
• When we notice random coincidences, we may forget
  that they are random and instead see them as
  correlated

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Illusory Correlations

• The sequential occurrence of two highly unusual
  events is most likely to contribute to an
  illusory correlation

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Objective ELEVEN

• Explain the human tendency to perceive order in
  random

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Perceiving Order in Random Events

• The King James Version of the Bible was completed
  when William Shakespeare was 46 years old. In
  Psalm 46 of this translation, the 46th word is
  shake and the 46th word from the end is
  spear. Before concluding that the biblical
  translators were trying to be humorous with these
  specific word placements, you would be best
  advised to recognise the danger of

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Perceiving Order in Random Events

• Perceiving Order in Random Events

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Perceiving Order in Random Events

• Perceiving Order in Random Events
• We know that illusory correlations arise from our
  natural eagerness to make sense of our world
• Poet Wallace Stevens called our rage for order
• We usually do find meaningful patterns because
  random sequences often dont look random

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Perceiving Order in Random Events

• Perceiving Order in Random Events
• Coin Toss Activity
• One student to board to record
• One student flips coin

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Statistical Reasoning
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The steps of the Scientific Method are

• Question
• Research
• Hypothesis
• Procedure/Method
• Data
• Observations
• Conclusion

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Statistical Data

• Doubt big, round, undocumented numbers.
• Doubt top-of-the-head estimates.
• Focus on thinking smarter by applying simple
  statistical principles to everyday reasoning

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Objective FIFTEEN

• Explain the importance of statistical principles
  and give an example of their use in everyday life
  

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Describing Data

• Once gathered (data) the first task is to
  organize them
• Bar graphs display a distribution
• Careful of interpreting graphs as the originator
  may have designed the graph to look small or
  large purposely
• Think smart
• Read the scale labels and note their range

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Objective SEVENTEEN

• Describe the three measures of central tendency
  and tell which is most affected by extreme scores

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Measures of Central Tendency

• Mean
• In mathematics and statistics, the arithmetic
  mean of a set of numbers is the sum of all the
  members of the set divided by the number of items
  in the set. (The word set is used perhaps
  somewhat loosely for example, the number 3.8
  could occur more than once in such a "set".) The
  arithmetic mean is what pupils are taught very
  early to call the "average." If the set is a
  statistical population, then we speak of the
  population mean

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Measures of Central Tendency

• Mean
• In a distribution of test scores, which measure
  of central tendency would likely be the most
  affected by a couple of extremely high scores?

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Measures of Central Tendency

• Mean
• In a distribution of test scores, which measure
  of central tendency would likely be the most
  affected by a couple of extremely high scores?
• MEAN

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Measures of Central Tendency

• Median
• The median is the score that divides the
  distribution into halves half of the scores are
  above the median and half are below it when the
  data are arranged in numerical order. The median
  is also referred to as the score at the 50 th
  percentile in the distribution. The median
  location of N numbers can be found by the formula
  (N 1) / 2. When N is an odd number, the formula
  yields a integer that represents the value in a
  numerically ordered distribution corresponding to
  the median location

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Measures of Central Tendency

• Mode
• The mode of a distribution is simply defined as
  the most frequent or common score in the
  distribution. The mode is the point or value of X
  that corresponds to the highest point on the
  distribution. If the highest frequency is shared
  by more than one value, the distribution is said
  to be multimodal. It is not uncommon to see
  distributions that are bimodal reflecting peaks
  in scoring at two different points in the
  distribution.

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Measures of Central Tendency
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Skewed Distribution

• In probability theory and statistics, skewness is
  a measure of the asymmetry of the probability
  distribution of a real-valued random variable.
  Roughly speaking, a distribution has positive
  skew (right-skewed) if the higher tail is longer
  and negative skew (left-skewed) if the lower tail
  is longer (confusing the two is a common error).

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INTRODUCTION TO PSYCHOLOGY

• Why Study Psychology?

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Psychologists can test the hypotheses and refine
the theories using 1. Description 2.
Correlation 3. Experimental Methods
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OPERATIONAL DEFINITION

• Operational Definition A statement of the
  procedures or ways in which a researcher is going
  to measure behaviors or qualities.
• For example, let's say you wanted measure and
  define "life change".
• You could do this by giving people the Social
  Readjustment Rating Scale and then operationally
  define "life change" as the score on the social
  readjustment rating scale.

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CORRELATIONAL STUDY

• A correlational study might look at variables
  that cannot be manipulated for the purposes of
  the study.
• For instance, is height correlated with how much
  people earn? Or, is intelligence correlated with
  marital happiness?
• You would be giving subjects tests and surveys to
  answer these questions, but could not manipulate
  the variables.

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EXPERIMENT

• An experimental study involves comparing two
  groups - and manipulating the variables.
• For instance, let's say the question is, "Does
  caffeine improve test performance?"
• Group 1 would have your subjects come to the lab
  and take some kind of test, making sure that they
  had had no caffeine within the last 24 hours, or
  some such scenario.
• Group 2 would have the same group of subjects
  come to the lab, drink a cup of coffee (or
  something) 20 minutes before taking a similar
  version of the first test (so there are no
  practice effects), and then comparing Group 1 and
  Group 2's scores to see if there was any
  significant difference.

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Correlation

• Correlation research is most useful for purposes
  of prediction
• Correlation if NOT CAUSATION
• Surveys and Naturalistic Observations
• When one or more traits or behavior accompanies
  another, we
  say they correlate

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Correlation

• Correlation coefficient
• Is a statistical measure of a relationship
• It reveals how closely two things vary together
  and how well either one predicts the other
• Example Know how much aptitude test scores
  correlate with school success tells us how well
  the scores predict school success

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Correlation

• Scatterplot
• A graph cluster of dots, each of which represents
  the values of two variables.
• The slope of the points suggests the direction of
  the relationship between the two variables
• The amount of scatter suggests the strength of
  the correlations (little scatter indicates high
  correlation)
• The REGRESSION LINE is the line of best fit for a
  set of scores plotted on a scatterplot

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Objective FOURTEEN

• Explain the difference between an independent and
  a dependent variable

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Independent and Dependent Variables

• An INDEPENDENT VARIABLE is a variable that is
  manipulated, measured, or selected by the
  researcher as an antecedent condition to an
  observed behavior.
• In a hypothesized cause-and-effect relationship,
  the independent variable is the cause and the
  dependent variable is the outcome or effect.

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Independent and Dependent Variables

• A DEPENDENT VARIABLE is a variable that is not
  under the experimenter's control -- the data.
• It is the variable that is observed and measured
  in response to the independent variable.

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Independent and Dependent Variables

• A variable is anything that can vary
• Experiments aim to manipulate an independent
  variable, measure the dependent variable, and
  control all other variables
• An experiment has at least two different
  conditions an experimental condition and a
  comparison or control condition

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Objective EIGHTEEN

• Describe two measures of variation

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Measures of Variation

• Knowing the value of an appropriate measure of
  central tendency can tell us a great deal
• However, you need to know a little about the
  amount of variation in the data how similar or
  diverse the scores are
• Averages derived from scores with low variability
  are more reliable than averages based on scores
  with high variability
• Example Basketball player scoring between 13
  17 points in first 10 games than say 5 25
  points

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Measures of Variation

• The RANGE of scores the gap between the lowest
  and highest scores provides a crude estimate of
  variation (but be carefule because a couple of
  extreme scores in an otherwise uniform groups
  will create a deceptively large range)
• The STANDARD DEVIATION is more useful measuring
  how much scores deviate from one another

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ETHICS

• American Psychological Association (1992)
• Shared statement of purpose with voluntary
  participants
• Obtain the informed consent of potential
  participants
• Protect them from harm and discomfort
• Treat information about individual participants
  confidentially
• Explain fully the research afterward

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Measures of Variation

• A measure of the range of variation from an
  average of a group of measurements.
• 68 of all measurements fall within one standard
  deviation of the average. 95 of all measurements
  fall within two standard deviations of the
  average

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Experimentation
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Objective TWELVE

• Explain how experimentation help researchers
  isolate cause and effect

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Exploring Cause and Effect

• The clearest and cleanest way to isolate cause
  and effect is, however, to experiment
• Experiments enable a researcher to focus on the
  possible effects of one or more factors by
• Manipulating the factors of interest and
• Holding constant (controlling) other factors

123
Exploring Cause and Effect

• Experiment (breast-fed infants and intelligence
  versus bottle-fed infants and intelligence)
• English experiment (1998)
• Mothers milk correlates modestly but positively
  with later intelligence
• 424 hospital preterm infants
• Parental permission
• Researchers randomly assigned some infants to the
  usual infant formula feedings and others to
  donated breast milk feedings
• When given intelligence tests at age 8, the
  children nourished with breast milk had
  significantly higher intelligence scores than
  their formula-fed counterparts

124
Exploring Cause and Effect

• The most foolproof way of testing the true
  effectiveness of a newly introduced method of
  psychological therapy is by means of

125
Objective THIRTEEN

• Explain why the double-blind procedure and random
  assignment build confidence in research findings

126
Exploring Cause and Effect

• Unlike correlational studies, which uncover
  naturally occurring relationships, an experiment
  manipulates a factor to determine its effect

127
Evaluating Therapies

• Psychologists may evaluate new therapy by
  employing participants who are blind about what
  treatment they are receiving.
• One group my receive the treatment the other
  receives a pseudotreatment an inert placebo
• Another method is a double-blind procedure (both
  researchers and participants are unaware) and may
  show signs of a placebo effect

128
Evaluating Therapies

• In an experiment designed to study the
  effectiveness of a new drug, research
  participants who receive a placebo are
  participating in what is called the CONTROLLED
  condition.

129
Evaluating Therapies

• Random assignment is assignment by chance, like
  flipping a coin or pulling numbers out of a hat.
• This method is sometimes used to determine who is
  in the experimental group and who is in the
  control group.
• For example, in a study with random assignment to
  one of two groups, participants have a 50 chance
  of being assigned to either group.

130
Evaluating Therapies

• The double-blind procedure is one way to create
  an experimental condition in which people receive
  the treatment and a contrasting control condition
  without the treatment
• By randomly assigning people to these conditions,
  researchers can be fairly certain the two groups
  are otherwise identical
• Random assignment roughly equalizes the two
  groups in ages, attitudes and other
  characteristic

131
Evaluating Therapies

• In a study of the effects of alcohol consumption,
  some participants drank a nonalcoholic beverage
  that actually smelled and tested like alcohol.
  This nonalcoholic drink was a

132
Evaluating Therapies

• In a study of the effects of alcohol consumption,
  some participants drank a nonalcoholic beverage
  that actually smelled and tested like alcohol.
  This nonalcoholic drink was a
• PLACEBO

133
Evaluating Therapies

• Both the researchers and the participants in a
  memory study are ignorant about which
  participants have actually received a potentially
  memory-enhancing drug and which have received a
  placebo. This investigation involves the use of
  the

134
Evaluating Therapies

• Both the researchers and the participants in a
  memory study are ignorant about which
  participants have actually received a potentially
  memory-enhancing drug and which have received a
  placebo. This investigation involves the use of
  the
• DOUBLE-BLIND PROCEDURE

135
Objective FOURTEEN

• Explain the difference between an independent and
  a dependent variable

136
Independent and Dependent Variables

• Viagra experiment (1998)
• 69 of Viagra-assisted attempts at intercourse
  were successful, compared to 22 for men
  receiving the placebo
• The experiment manipulated one drug factor which
  is called the independent variable
• The dependent variable (outcome factor) may
  change in response to manipulations of the
  independent variable

137
Independent and Dependent Variables

• An INDEPENDENT VARIABLE is a variable that is
  manipulated, measured, or selected by the
  researcher as an antecedent condition to an
  observed behavior. In a hypothesized
  cause-and-effect relationship, the independent
  variable is the cause and the dependent variable
  is the outcome or effect.

138
Independent and Dependent Variables

• A DEPENDENT VARIABLE is a variable that is not
  under the experimenter's control -- the data. It
  is the variable that is observed and measured in
  response to the independent variable.

139
Independent and Dependent Variables

• A variable is anything that can vary
• Experiments aim to manipulate an independent
  variable, measure the dependent variable, and
  control all other variables
• An experiment has at least two different
  conditions an experimental condition and a
  comparison or control condition

140
Statistical Reasoning
141
The steps of the Scientific Method are

• Question
• Research
• Hypothesis
• Procedure/Method
• Data
• Observations
• Conclusion

142
Statistical Data

• Doubt big, round, undocumented numbers.
• Doubt top-of-the-head estimates.
• Focus on thinking smarter by applying simple
  statistical principles to everyday reasoning

143
Objective FIFTEEN

• Explain the importance of statistical principles
  and give an example of their use in everyday life
  

144
Describing Data

• Once gathered (data) the first task is to
  organize them
• Bar graphs display a distribution
• Careful of interpreting graphs as the originator
  may have designed the graph to look small or
  large purposely
• Think smart
• Read the scale labels and note their range

145
Objective SEVENTEEN

• Describe the three measures of central tendency
  and tell which is most affected by extreme scores

146
Measures of Central Tendency

• Mean
• In mathematics and statistics, the arithmetic
  mean of a set of numbers is the sum of all the
  members of the set divided by the number of items
  in the set. (The word set is used perhaps
  somewhat loosely for example, the number 3.8
  could occur more than once in such a "set".) The
  arithmetic mean is what pupils are taught very
  early to call the "average." If the set is a
  statistical population, then we speak of the
  population mean

147
Measures of Central Tendency

• Mean
• In a distribution of test scores, which measure
  of central tendency would likely be the most
  affected by a couple of extremely high scores?

148
Measures of Central Tendency

• Mean
• In a distribution of test scores, which measure
  of central tendency would likely be the most
  affected by a couple of extremely high scores?
• MEAN

149
Measures of Central Tendency

• Median
• The median is the score that divides the
  distribution into halves half of the scores are
  above the median and half are below it when the
  data are arranged in numerical order. The median
  is also referred to as the score at the 50 th
  percentile in the distribution. The median
  location of N numbers can be found by the formula
  (N 1) / 2. When N is an odd number, the formula
  yields a integer that represents the value in a
  numerically ordered distribution corresponding to
  the median location

150
Measures of Central Tendency

• Mode
• The mode of a distribution is simply defined as
  the most frequent or common score in the
  distribution. The mode is the point or value of X
  that corresponds to the highest point on the
  distribution. If the highest frequency is shared
  by more than one value, the distribution is said
  to be multimodal. It is not uncommon to see
  distributions that are bimodal reflecting peaks
  in scoring at two different points in the
  distribution.

151
Measures of Central Tendency
152
Skewed Distribution

• In probability theory and statistics, skewness is
  a measure of the asymmetry of the probability
  distribution of a real-valued random variable.
  Roughly speaking, a distribution has positive
  skew (right-skewed) if the higher tail is longer
  and negative skew (left-skewed) if the lower tail
  is longer (confusing the two is a common error).

153
Objective EIGHTEEN

• Describe two measures of variation

154
Measures of Variation

• Knowing the value of an appropriate measure of
  central tendency can tell us a great deal
• However, you need to know a little about the
  amount of variation in the data how similar or
  diverse the scores are
• Averages derived from scores with low variability
  are more reliable than averages based on scores
  with high variability
• Example Basketball player scoring between 13
  17 points in first 10 games than say 5 25
  points

155
Measures of Variation

• The RANGE of scores the gap between the lowest
  and highest scores provides a crude estimate of
  variation (but be carefule because a couple of
  extreme scores in an otherwise uniform groups
  will create a deceptively large range)
• The STANDARD DEVIATION is more useful measuring
  how much scores deviate from one another

156
Measures of Variation

• A measure of the range of variation from an
  average of a group of measurements.
• 68 of all measurements fall within one standard
  deviation of the average. 95 of all measurements
  fall within two standard deviations of the
  average

157
Making Inferences
158
Objective NINETEEN

• Identify three principles for making
  generalizations from samples

159
When is an Observed Difference Reliable?

• THREE principles
• Representative samples are better than biased
  samples
• Pays to keep in mind what population a study has
  sampled
• Less-variable observations are more reliable than
  those that are more variable
• - an average is better with low variability
• 3. More cases are better than fewer

160
Objective TWENTY

• Explain how psychologists decide whether
  differences are meaningful

161
When is a Difference Significant?

• Statistical tests also help psychologists
  determine whether differences are meaningful
• When averages from two samples are each reliable
  measures of their respective populations, then
  their difference is likely to be reliable as well

162
When is a Difference Significant?

• When the sample averages are reliable and the
  difference between them is relatively large,
  psychologists say the difference has statistical
  significance because the difference observed is
  probably not due to chance variation between the
  samples
• Statistical significance does not mean that the
  results automatically have practical significance
  or importance

163
Frequently Asked Questions About Psychology
164
Objective TWENTY-ONE

• Explain the value of simplified laboratory
  conditions in discovering general principles of
  behavior

165
Can Laboratory Experiments illuminate Everyday
Life?

• Psychologist (researchers) intends the laboratory
  environment to be a simplified reality one that
  stimulates and controls important features of
  everyday life
• Hope is that the laboratory experiment enables a
  psychologists to re-create psychological forces
  under controlled conditions

166
Objective TWENTY-TWO

• Discuss whether psychological research can be
  generalized across cultures and genders

167
Does Behavior Depend on Ones Culture

• Culture shared ideas and behaviors that one
  generation passes on to the next matters
• Our culture influences our standards of
  promptness and frankness, our attitudes toward
  values, ethics, morals and standards
• With the growing (mixing and clashing) diversity
  in America, our awareness is urgent

168
Does Behavior Depend on Ones Culture

• An awareness of extensive cultural differences in
  attitudes and values is most helpful for
  avoidingthe false consensus effect
• The false consensus effect refers to the tendency
  for people to overestimate the degree to which
  others agree with them. People readily guess
  their own opinions, beliefs and predilections as
  being more prevalent in the general public than
  they really are. The bias is commonly present in
  a group setting where one thinks the collective
  opinion of their own group matches that of the
  larger population.

169
Does Behavior Vary with Gender

• Psychological differences between the genders are
  far outweighed by gender similarities

170
Objective TWENTY-THREE

• Explain why psychologists study animals and
  discuss the ethics of experimentation with both
  animals and humans

171
Why do Psychologists Study Animals?

• They want to understand how different species
  learn, think and behave to learn about people
• Human physiology resembles that on many animals
• We humans are animals?
• Experimentation on animals leading to cures in
  diseases, insulin for diabetes, vaccines to
  prevent polio and rabies, transplnats to replace
  human defective organs

172
Is it Ethical to Experiment on Animals?

• If we share similarities with other animals, they
  should be respect them?
• We cannot defend our scientific work with
  animals on the basis of the similarities between
  them and ourselves on the basis of the
  similarities between them and ourselves and then
  defend it morally on the battle of differences?

173
Is it Ethical to Experiment on Animals?

• Research
• 30 million mammals /year
• 1 of the billions killed each year for food
• Average person eats 20 animals a year
• 200,000 dogs and cats (under humane regulations)
• Over 1 million are killed in humane societies
  each year
• Psychologists for the Ethical Treatment of Animals

174
Is it Ethical to Experiment on Animals?

• Psychologists for the Ethical Treatment of
  Animals
• Advocate naturalistic observation of animals
  rather than laboratory manipulation
• 60 of Americans deem animal research valid but
  37 of British do
• Two issues emerge
• Is it right to place the well-being of humans
  above that of animals
• What is the priority we give to the well-being of
  animals in research?

175
Is it Ethical to Experiment on People?

• The American Psychological Association and
  British Psychological Society
• Obtain consent
• Protect them from harm and discomfort
• Treat information confidentially
• Fully explain the research afterwards

176
Objective TWENTY-FOUR

• Describe how personal values can influence
  psychologists research and its application, and
  discuss psychologys potential to manipulate
  people

177
Is Psychology Free of Value Judgments?

• It is not value-free
• Values affect what we study, how we study and how
  we interpret results
• Influence what research topics are studies
• Preconceptions can
  bias observations
  and interpretations

178
Is Psychology Free of Value Judgments?
179
Is Psychology Potentially Dangerous?

• Knowledge can be used for good or evil
• Educate or deceive?
• Help or manipulate?
• Restore sanity or destroy it?

180
Florida

1. I feel __ certain that the number of counties in
   Florida is more than ____ but less than ____
2. I feel __ certain that the number of Senate
   Districts in Florida is more than ____ but less
   than ____
3. I feel __ certain that the percentage of all US
   exports to Latin and South America pass through
   Florida is more than ____ but less than ____
4. I feel __ certain that the area of Florida is
   more than ____ sq miles but less than ____ square
   miles
5. I feel __ certain that the 2005 population of
   Melbourne was more than ____ but less than ____

181
DEMONSTRATION

• (stds) X (questions) X 0.00 (error rate)
  ?

182
Florida

1. I feel __ certain that the number of counties in
   Florida is more than ____ but less than ____ (67
   counties)
2. I feel __ certain that the number of Senate
   Districts in Florida is more than ____ but less
   than ____ (40 Senate Districts)
3. I feel __ certain that the percentage of all US
   exports to Latin and South America pass through
   Florida is more than ____ but less than ____
   (40)
4. I feel __ certain that the area of Florida is
   more than ____ sq miles but less than ____ square
   miles (58, 560 sq mi)
5. I feel __ certain that the 2005 population of
   Melbourne was more than ____ but less than ____
   (476,0000)

183
UNCOMMON SENSE

• If you drop a bullet off a table 3 ft high, and
  fire another one straight across an empty
  football field, which hits the ground first?

184
UNCOMMON SENSE

• If you drop a bullet off a table 3 ft high, and
  fire another one straight across an empty
  football field, which hits the ground first?

• Both bullets hit at the same time because
  downward velocity is independent of horizontal
  velocity

185
UNCOMMON SENSE

• A wooden cube is 1-inch long on each side. How
  many cubes form a cube 2 inches along each side?

186
UNCOMMON SENSE

• A wooden cube is 1-inch long on each side. How
  many cubes form a cube 2 inches along each side?

• The solution is actually 8. Two cubes make a
  tower. For a cube you need two layers of 4

187
Chapter ONE Objectives

• define hindsight bias, and explain how it can
  make research findings seem like mere common
  sense
• describe how overconfidence contaminates our
  everyday judgments
• explain how the scientific attitude encourages
  critical thinking
• describe how psychological theories guide
  scientific research
• identify an advantage and a disadvantage of using
  case studies to study behavior
• identify the advantages and disadvantages of
  using surveys to study behavior and mental
  processes, and explain the importance of working
  effects and random sampling

188
Chapter ONE Objectives

• identify an advantage and a disadvantage of using
  naturalistic observation to study behavior
• describe positive and negative correlations, and
  explain how correlational measures can aid the
  process of prediction
• explain why correlational research fails to
  provide evidence of cause-effect relationships
• describe how people form illusory correlations
• explain the human tendency to perceive order in
  random sequences

189
Chapter ONE Objectives

• explain how experiments help researchers isolate
  cause and effect
• explain why the double procedure and random
  assignment build confidence in research findings
• explain the difference between an independent and
  dependent variable
• explain the importance of statistical principles,
  and give an example of their use in everyday life
• explain how bar graphs can misrepresent data

190
Chapter ONE Objectives

• describe the three measure of central tendency,
  and tell which is most affected by extreme scores
• describe two measures of variation
• identify three principles of making
  generalizations from samples
• explain how psychologists decide whether
  differences are meaningful
• explain the value of simplified laboratory
  conditions in discovering general principles of
  behavior

191
Chapter ONE Objectives

• discuss whether psychological research can be
  generalized across cultures and genders
• explain why psychologists study animals, and
  discuss the ethics of experimentation with both
  animals and humans

192
Empirical Evidence

• What is it?
• Information gained from direct observation
• Psychologists study behavior directly and collect
  data (observed facts) so that they can draw valid
  conclusions
• Its great strength is that it uses the
  Scientific Method
• Rene Descartes
• Sir Francis Bacon
• Can only be DEDUCTIVE and INDUCTIVE in searching
  of truth
• William Wundt
• Observation
• Edmund Titchener
• Structuralism

193
Scientific Method Valid Reasoning

• While inductive reasoning argues from the
  particular to the general, deductive reasoning
  argues from the general to a specific
• EMPIRICAL DATA are DATA that are produced by
  EXPERIMENT or OBSERVATION

194
DEMONSTRATION
195
DEMONSTRATION

• John Brink

196
DEMONSTRATION

• DO NOT TURN the paper over until I tell you so
• Write your level of confidence () of what you
  will receive on the 10-QUESTION T/F PROLOGUE QUIZ

197
AP PSYCHOLOGY PROLOGUE
198
PROLOGUE QUIZ

1. F
2. T
3. T
4. F
5. T

• 6. T