- •Preface
- •Approach and Pedagogy
- •Chapter 1
- •Introducing Psychology
- •1.1 Psychology as a Science
- •The Problem of Intuition
- •Research Focus: Unconscious Preferences for the Letters of Our Own Name
- •Why Psychologists Rely on Empirical Methods
- •Levels of Explanation in Psychology
- •The Challenges of Studying Psychology
- •1.2 The Evolution of Psychology: History, Approaches, and Questions
- •Early Psychologists
- •Structuralism: Introspection and the Awareness of Subjective Experience
- •Functionalism and Evolutionary Psychology
- •Psychodynamic Psychology
- •Behaviorism and the Question of Free Will
- •Research Focus: Do We Have Free Will?
- •The Cognitive Approach and Cognitive Neuroscience
- •The War of the Ghosts
- •Social-Cultural Psychology
- •The Many Disciplines of Psychology
- •Psychology in Everyday Life: How to Effectively Learn and Remember
- •1.3 Chapter Summary
- •Chapter 2
- •Psychological Science
- •Psychological Journals
- •2.1 Psychologists Use the Scientific Method to Guide Their Research
- •The Scientific Method
- •Laws and Theories as Organizing Principles
- •The Research Hypothesis
- •Conducting Ethical Research
- •Characteristics of an Ethical Research Project Using Human Participants
- •Ensuring That Research Is Ethical
- •Research With Animals
- •APA Guidelines on Humane Care and Use of Animals in Research
- •Descriptive Research: Assessing the Current State of Affairs
- •Correlational Research: Seeking Relationships Among Variables
- •Experimental Research: Understanding the Causes of Behavior
- •Research Focus: Video Games and Aggression
- •2.3 You Can Be an Informed Consumer of Psychological Research
- •Threats to the Validity of Research
- •Psychology in Everyday Life: Critically Evaluating the Validity of Websites
- •2.4 Chapter Summary
- •Chapter 3
- •Brains, Bodies, and Behavior
- •Did a Neurological Disorder Cause a Musician to Compose Boléro and an Artist to Paint It 66 Years Later?
- •3.1 The Neuron Is the Building Block of the Nervous System
- •Neurons Communicate Using Electricity and Chemicals
- •Video Clip: The Electrochemical Action of the Neuron
- •Neurotransmitters: The Body’s Chemical Messengers
- •3.2 Our Brains Control Our Thoughts, Feelings, and Behavior
- •The Old Brain: Wired for Survival
- •The Cerebral Cortex Creates Consciousness and Thinking
- •Functions of the Cortex
- •The Brain Is Flexible: Neuroplasticity
- •Research Focus: Identifying the Unique Functions of the Left and Right Hemispheres Using Split-Brain Patients
- •Psychology in Everyday Life: Why Are Some People Left-Handed?
- •3.3 Psychologists Study the Brain Using Many Different Methods
- •Lesions Provide a Picture of What Is Missing
- •Recording Electrical Activity in the Brain
- •Peeking Inside the Brain: Neuroimaging
- •Research Focus: Cyberostracism
- •3.4 Putting It All Together: The Nervous System and the Endocrine System
- •Electrical Control of Behavior: The Nervous System
- •The Body’s Chemicals Help Control Behavior: The Endocrine System
- •3.5 Chapter Summary
- •Chapter 4
- •Sensing and Perceiving
- •Misperception by Those Trained to Accurately Perceive a Threat
- •4.1 We Experience Our World Through Sensation
- •Sensory Thresholds: What Can We Experience?
- •Link
- •Measuring Sensation
- •Research Focus: Influence without Awareness
- •4.2 Seeing
- •The Sensing Eye and the Perceiving Visual Cortex
- •Perceiving Color
- •Perceiving Form
- •Perceiving Depth
- •Perceiving Motion
- •Beta Effect and Phi Phenomenon
- •4.3 Hearing
- •Hearing Loss
- •4.4 Tasting, Smelling, and Touching
- •Tasting
- •Smelling
- •Touching
- •Experiencing Pain
- •4.5 Accuracy and Inaccuracy in Perception
- •How the Perceptual System Interprets the Environment
- •Video Clip: The McGurk Effect
- •Video Clip: Selective Attention
- •Illusions
- •The Important Role of Expectations in Perception
- •Psychology in Everyday Life: How Understanding Sensation and Perception Can Save Lives
- •4.6 Chapter Summary
- •Chapter 5
- •States of Consciousness
- •An Unconscious Killing
- •5.1 Sleeping and Dreaming Revitalize Us for Action
- •Research Focus: Circadian Rhythms Influence the Use of Stereotypes in Social Judgments
- •Sleep Stages: Moving Through the Night
- •Sleep Disorders: Problems in Sleeping
- •The Heavy Costs of Not Sleeping
- •Dreams and Dreaming
- •5.2 Altering Consciousness With Psychoactive Drugs
- •Speeding Up the Brain With Stimulants: Caffeine, Nicotine, Cocaine, and Amphetamines
- •Slowing Down the Brain With Depressants: Alcohol, Barbiturates and Benzodiazepines, and Toxic Inhalants
- •Opioids: Opium, Morphine, Heroin, and Codeine
- •Hallucinogens: Cannabis, Mescaline, and LSD
- •Why We Use Psychoactive Drugs
- •Research Focus: Risk Tolerance Predicts Cigarette Use
- •5.3 Altering Consciousness Without Drugs
- •Changing Behavior Through Suggestion: The Power of Hypnosis
- •Reducing Sensation to Alter Consciousness: Sensory Deprivation
- •Meditation
- •Video Clip: Try Meditation
- •Psychology in Everyday Life: The Need to Escape Everyday Consciousness
- •5.4 Chapter Summary
- •Chapter 6
- •Growing and Developing
- •The Repository for Germinal Choice
- •6.1 Conception and Prenatal Development
- •The Zygote
- •The Embryo
- •The Fetus
- •How the Environment Can Affect the Vulnerable Fetus
- •6.2 Infancy and Childhood: Exploring and Learning
- •The Newborn Arrives With Many Behaviors Intact
- •Research Focus: Using the Habituation Technique to Study What Infants Know
- •Cognitive Development During Childhood
- •Video Clip: Object Permanence
- •Social Development During Childhood
- •Knowing the Self: The Development of the Self-Concept
- •Video Clip: The Harlows’ Monkeys
- •Video Clip: The Strange Situation
- •Research Focus: Using a Longitudinal Research Design to Assess the Stability of Attachment
- •6.3 Adolescence: Developing Independence and Identity
- •Physical Changes in Adolescence
- •Cognitive Development in Adolescence
- •Social Development in Adolescence
- •Developing Moral Reasoning: Kohlberg’s Theory
- •Video Clip: People Being Interviewed About Kohlberg’s Stages
- •6.4 Early and Middle Adulthood: Building Effective Lives
- •Psychology in Everyday Life: What Makes a Good Parent?
- •Physical and Cognitive Changes in Early and Middle Adulthood
- •Menopause
- •Social Changes in Early and Middle Adulthood
- •6.5 Late Adulthood: Aging, Retiring, and Bereavement
- •Cognitive Changes During Aging
- •Dementia and Alzheimer’s Disease
- •Social Changes During Aging: Retiring Effectively
- •Death, Dying, and Bereavement
- •6.6 Chapter Summary
- •Chapter 7
- •Learning
- •My Story of Posttraumatic Stress Disorder
- •7.1 Learning by Association: Classical Conditioning
- •Pavlov Demonstrates Conditioning in Dogs
- •The Persistence and Extinction of Conditioning
- •The Role of Nature in Classical Conditioning
- •How Reinforcement and Punishment Influence Behavior: The Research of Thorndike and Skinner
- •Video Clip: Thorndike’s Puzzle Box
- •Creating Complex Behaviors Through Operant Conditioning
- •7.3 Learning by Insight and Observation
- •Observational Learning: Learning by Watching
- •Video Clip: Bandura Discussing Clips From His Modeling Studies
- •Research Focus: The Effects of Violent Video Games on Aggression
- •7.4 Using the Principles of Learning to Understand Everyday Behavior
- •Using Classical Conditioning in Advertising
- •Video Clip: Television Ads
- •Psychology in Everyday Life: Operant Conditioning in the Classroom
- •Reinforcement in Social Dilemmas
- •7.5 Chapter Summary
- •Chapter 8
- •Remembering and Judging
- •She Was Certain, but She Was Wrong
- •Differences between Brains and Computers
- •Video Clip: Kim Peek
- •8.1 Memories as Types and Stages
- •Explicit Memory
- •Implicit Memory
- •Research Focus: Priming Outside Awareness Influences Behavior
- •Stages of Memory: Sensory, Short-Term, and Long-Term Memory
- •Sensory Memory
- •Short-Term Memory
- •8.2 How We Remember: Cues to Improving Memory
- •Encoding and Storage: How Our Perceptions Become Memories
- •Research Focus: Elaboration and Memory
- •Using the Contributions of Hermann Ebbinghaus to Improve Your Memory
- •Retrieval
- •Retrieval Demonstration
- •States and Capital Cities
- •The Structure of LTM: Categories, Prototypes, and Schemas
- •The Biology of Memory
- •8.3 Accuracy and Inaccuracy in Memory and Cognition
- •Source Monitoring: Did It Really Happen?
- •Schematic Processing: Distortions Based on Expectations
- •Misinformation Effects: How Information That Comes Later Can Distort Memory
- •Overconfidence
- •Heuristic Processing: Availability and Representativeness
- •Salience and Cognitive Accessibility
- •Counterfactual Thinking
- •Psychology in Everyday Life: Cognitive Biases in the Real World
- •8.4 Chapter Summary
- •Chapter 9
- •Intelligence and Language
- •How We Talk (or Do Not Talk) about Intelligence
- •9.1 Defining and Measuring Intelligence
- •General (g) Versus Specific (s) Intelligences
- •Measuring Intelligence: Standardization and the Intelligence Quotient
- •The Biology of Intelligence
- •Is Intelligence Nature or Nurture?
- •Psychology in Everyday Life: Emotional Intelligence
- •9.2 The Social, Cultural, and Political Aspects of Intelligence
- •Extremes of Intelligence: Retardation and Giftedness
- •Extremely Low Intelligence
- •Extremely High Intelligence
- •Sex Differences in Intelligence
- •Racial Differences in Intelligence
- •Research Focus: Stereotype Threat
- •9.3 Communicating With Others: The Development and Use of Language
- •The Components of Language
- •Examples in Which Syntax Is Correct but the Interpretation Can Be Ambiguous
- •The Biology and Development of Language
- •Research Focus: When Can We Best Learn Language? Testing the Critical Period Hypothesis
- •Learning Language
- •How Children Learn Language: Theories of Language Acquisition
- •Bilingualism and Cognitive Development
- •Can Animals Learn Language?
- •Video Clip: Language Recognition in Bonobos
- •Language and Perception
- •9.4 Chapter Summary
- •Chapter 10
- •Emotions and Motivations
- •Captain Sullenberger Conquers His Emotions
- •10.1 The Experience of Emotion
- •Video Clip: The Basic Emotions
- •The Cannon-Bard and James-Lange Theories of Emotion
- •Research Focus: Misattributing Arousal
- •Communicating Emotion
- •10.2 Stress: The Unseen Killer
- •The Negative Effects of Stress
- •Stressors in Our Everyday Lives
- •Responses to Stress
- •Managing Stress
- •Emotion Regulation
- •Research Focus: Emotion Regulation Takes Effort
- •10.3 Positive Emotions: The Power of Happiness
- •Finding Happiness Through Our Connections With Others
- •What Makes Us Happy?
- •10.4 Two Fundamental Human Motivations: Eating and Mating
- •Eating: Healthy Choices Make Healthy Lives
- •Obesity
- •Sex: The Most Important Human Behavior
- •The Experience of Sex
- •The Many Varieties of Sexual Behavior
- •Psychology in Everyday Life: Regulating Emotions to Improve Our Health
- •10.5 Chapter Summary
- •Chapter 11
- •Personality
- •Identical Twins Reunited after 35 Years
- •11.1 Personality and Behavior: Approaches and Measurement
- •Personality as Traits
- •Example of a Trait Measure
- •Situational Influences on Personality
- •The MMPI and Projective Tests
- •Psychology in Everyday Life: Leaders and Leadership
- •11.2 The Origins of Personality
- •Psychodynamic Theories of Personality: The Role of the Unconscious
- •Id, Ego, and Superego
- •Research Focus: How the Fear of Death Causes Aggressive Behavior
- •Strengths and Limitations of Freudian and Neo-Freudian Approaches
- •Focusing on the Self: Humanism and Self-Actualization
- •Research Focus: Self-Discrepancies, Anxiety, and Depression
- •Studying Personality Using Behavioral Genetics
- •Studying Personality Using Molecular Genetics
- •Reviewing the Literature: Is Our Genetics Our Destiny?
- •11.4 Chapter Summary
- •Chapter 12
- •Defining Psychological Disorders
- •When Minor Body Imperfections Lead to Suicide
- •12.1 Psychological Disorder: What Makes a Behavior “Abnormal”?
- •Defining Disorder
- •Psychology in Everyday Life: Combating the Stigma of Abnormal Behavior
- •Diagnosing Disorder: The DSM
- •Diagnosis or Overdiagnosis? ADHD, Autistic Disorder, and Asperger’s Disorder
- •Attention-Deficit/Hyperactivity Disorder (ADHD)
- •Autistic Disorder and Asperger’s Disorder
- •12.2 Anxiety and Dissociative Disorders: Fearing the World Around Us
- •Generalized Anxiety Disorder
- •Panic Disorder
- •Phobias
- •Obsessive-Compulsive Disorders
- •Posttraumatic Stress Disorder (PTSD)
- •Dissociative Disorders: Losing the Self to Avoid Anxiety
- •Dissociative Amnesia and Fugue
- •Dissociative Identity Disorder
- •Explaining Anxiety and Dissociation Disorders
- •12.3 Mood Disorders: Emotions as Illness
- •Behaviors Associated with Depression
- •Dysthymia and Major Depressive Disorder
- •Bipolar Disorder
- •Explaining Mood Disorders
- •Research Focus: Using Molecular Genetics to Unravel the Causes of Depression
- •12.4 Schizophrenia: The Edge of Reality and Consciousness
- •Symptoms of Schizophrenia
- •Explaining Schizophrenia
- •12.5 Personality Disorders
- •Borderline Personality Disorder
- •Research Focus: Affective and Cognitive Deficits in BPD
- •Antisocial Personality Disorder (APD)
- •12.6 Somatoform, Factitious, and Sexual Disorders
- •Somatoform and Factitious Disorders
- •Sexual Disorders
- •Disorders of Sexual Function
- •Paraphilias
- •12.7 Chapter Summary
- •Chapter 13
- •Treating Psychological Disorders
- •Therapy on Four Legs
- •13.1 Reducing Disorder by Confronting It: Psychotherapy
- •DSM-IV-TR Criteria for Diagnosing Attention-Deficit/Hyperactivity Disorder (ADHD)
- •Psychology in Everyday Life: Seeking Treatment for Psychological Difficulties
- •Psychodynamic Therapy
- •Important Characteristics and Experiences in Psychoanalysis
- •Humanistic Therapies
- •Behavioral Aspects of CBT
- •Cognitive Aspects of CBT
- •Combination (Eclectic) Approaches to Therapy
- •13.2 Reducing Disorder Biologically: Drug and Brain Therapy
- •Drug Therapies
- •Using Stimulants to Treat ADHD
- •Antidepressant Medications
- •Antianxiety Medications
- •Antipsychotic Medications
- •Direct Brain Intervention Therapies
- •13.3 Reducing Disorder by Changing the Social Situation
- •Group, Couples, and Family Therapy
- •Self-Help Groups
- •Community Mental Health: Service and Prevention
- •Some Risk Factors for Psychological Disorders
- •Research Focus: The Implicit Association Test as a Behavioral Marker for Suicide
- •13.4 Evaluating Treatment and Prevention: What Works?
- •Effectiveness of Psychological Therapy
- •Research Focus: Meta-Analyzing Clinical Outcomes
- •Effectiveness of Biomedical Therapies
- •Effectiveness of Social-Community Approaches
- •13.5 Chapter Summary
- •Chapter 14
- •Psychology in Our Social Lives
- •Binge Drinking and the Death of a Homecoming Queen
- •14.1 Social Cognition: Making Sense of Ourselvesand Others
- •Perceiving Others
- •Forming Judgments on the Basis of Appearance: Stereotyping, Prejudice, and Discrimination
- •Implicit Association Test
- •Research Focus: Forming Judgments of People in Seconds
- •Close Relationships
- •Causal Attribution: Forming Judgments by Observing Behavior
- •Attitudes and Behavior
- •14.2 Interacting With Others: Helping, Hurting, and Conforming
- •Helping Others: Altruism Helps Create Harmonious Relationships
- •Why Are We Altruistic?
- •How the Presence of Others Can Reduce Helping
- •Video Clip: The Case of Kitty Genovese
- •Human Aggression: An Adaptive yet Potentially Damaging Behavior
- •The Ability to Aggress Is Part of Human Nature
- •Negative Experiences Increase Aggression
- •Viewing Violent Media Increases Aggression
- •Video Clip
- •Research Focus: The Culture of Honor
- •Conformity and Obedience: How Social Influence Creates Social Norms
- •Video Clip
- •Do We Always Conform?
- •14.3 Working With Others: The Costs and Benefits of Social Groups
- •Working in Front of Others: Social Facilitation and Social Inhibition
- •Working Together in Groups
- •Psychology in Everyday Life: Do Juries Make Good Decisions?
- •Using Groups Effectively
- •14.4 Chapter Summary
2.1 Psychologists Use the Scientific Method to Guide Their Research
L E A R N I N G O B J E C T I V E S
1.Describe the principles of the scientific method and explain its importance in conducting and interpreting research.
2.Differentiate laws from theories and explain how research hypotheses are developed and tested.
3.Discuss the procedures that researchers use to ensure that their research with humans and with animals is ethical.
Psychologists aren’t the only people who seek to understand human behavior and solve social problems. Philosophers, religious leaders, and politicians, among others, also strive to provide explanations for human behavior. But psychologists believe that research is the best tool for understanding human beings and their relationships with others. Rather than accepting the claim of a philosopher that people do (or do not) have free will, a psychologist would collect data to empirically test whether or not people are able to actively control their own behavior. Rather than accepting a politician’s contention that creating (or abandoning) a new center for mental health will improve the lives of individuals in the inner city, a psychologist would empirically assess the effects of receiving mental health treatment on the quality of life of the recipients. The statements made by psychologists are empirical, which means they are based on systematic collection and analysis of data.
The Scientific Method
All scientists (whether they are physicists, chemists, biologists, sociologists, or psychologists) are engaged in the basic processes of collecting data and drawing conclusions about those data. The methods used by scientists have developed over many years and provide a common framework for developing, organizing, and sharing information. The scientific method is the set of assumptions, rules, and procedures scientists use to conduct research.
In addition to requiring that science be empirical, the scientific method demands that the procedures used be objective, or free from the personal bias or emotions of the scientist. The scientific method proscribes how scientists collect and analyze data, how they draw conclusions from data, and how they share data with others. These rules increase objectivity by placing data under the scrutiny of other scientists and even the public at large. Because data are reported objectively, other scientists know exactly how the scientist collected and analyzed the data. This
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means that they do not have to rely only on the scientist’s own interpretation of the data; they may draw their own, potentially different, conclusions.
Most new research is designed to replicate—that is, to repeat, add to, or modify—previous research findings. The scientific method therefore results in an accumulation of scientific knowledge through the reporting of research and the addition to and modifications of these reported findings by other scientists.
Laws and Theories as Organizing Principles
One goal of research is to organize information into meaningful statements that can be applied in many situations. Principles that are so general as to apply to all situations in a given domain of inquiry are known as laws. There are well-known laws in the physical sciences, such as the law of gravity and the laws of thermodynamics, and there are some universally accepted laws in psychology, such as the law of effect and Weber’s law. But because laws are very general principles and their validity has already been well established, they are themselves rarely directly subjected to scientific test.
The next step down from laws in the hierarchy of organizing principles is theory. A theory is an integrated set of principles that explains and predicts many, but not all, observed relationships within a given domain of inquiry. One example of an important theory in psychology is the stage theory of cognitive development proposed by the Swiss psychologist Jean Piaget. The theory states that children pass through a series of cognitive stages as they grow, each of which must be mastered in succession before movement to the next cognitive stage can occur. This is an extremely useful theory in human development because it can be applied to many different content areas and can be tested in many different ways.
Good theories have four important characteristics. First, good theories are general, meaning they summarize many different outcomes. Second, they are parsimonious, meaning they provide the simplest possible account of those outcomes. The stage theory of cognitive development meets both of these requirements. It can account for developmental changes in behavior across a wide variety of domains, and yet it does so parsimoniously—by hypothesizing a simple set of cognitive stages. Third, good theories provide ideas for future research. The stage theory of
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cognitive development has been applied not only to learning about cognitive skills, but also to the study of children’s moral (Kohlberg, 1966) [1] and gender (Ruble & Martin,
1998) [2] development.
Finally, good theories are falsifiable (Popper, 1959), [3] which means the variables of interest can be adequately measured and the relationships between the variables that are predicted by the theory can be shown through research to be incorrect. The stage theory of cognitive development is falsifiable because the stages of cognitive reasoning can be measured and because if research discovers, for instance, that children learn new tasks before they have reached the cognitive stage hypothesized to be required for that task, then the theory will be shown to be incorrect.
No single theory is able to account for all behavior in all cases. Rather, theories are each limited in that they make accurate predictions in some situations or for some people but not in other situations or for other people. As a result, there is a constant exchange between theory and data: Existing theories are modified on the basis of collected data, and the new modified theories then make new predictions that are tested by new data, and so forth. When a better theory is found, it will replace the old one. This is part of the accumulation of scientific knowledge.
The Research Hypothesis
Theories are usually framed too broadly to be tested in a single experiment. Therefore, scientists use a more precise statement of the presumed relationship among specific parts of a theory—a research hypothesis—as the basis for their research. A research hypothesis is a specific and falsifiable prediction about the relationship between or among two or more variables, where
a variable is any attribute that can assume different values among different people or across different times or places. The research hypothesis states the existence of a relationship between the variables of interest and the specific direction of that relationship. For instance, the research hypothesis “Using marijuana will reduce learning” predicts that there is a relationship between a variable “using marijuana” and another variable called “learning.” Similarly, in the research hypothesis “Participating in psychotherapy will reduce anxiety,” the variables that are expected to be related are “participating in psychotherapy” and “level of anxiety.”
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When stated in an abstract manner, the ideas that form the basis of a research hypothesis are known as conceptual variables. Conceptual variables are abstract ideas that form the basis of research hypotheses. Sometimes the conceptual variables are rather simple—for instance, “age,” “gender,” or “weight.” In other cases the conceptual variables represent more complex ideas, such as “anxiety,” “cognitive development,” “learning,” self-esteem,” or “sexism.”
The first step in testing a research hypothesis involves turning the conceptual variables
into measured variables, which are variables consisting of numbers that represent the conceptual variables. For instance, the conceptual variable “participating in psychotherapy” could be represented as the measured variable “number of psychotherapy hours the patient has accrued” and the conceptual variable “using marijuana” could be assessed by having the research participants rate, on a scale from 1 to 10, how often they use marijuana or by administering a blood test that measures the presence of the chemicals in marijuana.
Psychologists use the term operational definition to refer to a precise statement of how a conceptual variable is turned into a measured variable. The relationship between conceptual and measured variables in a research hypothesis is diagrammed in Figure 2.1 "Diagram of a Research Hypothesis". The conceptual variables are represented within circles at the top of the figure, and the measured variables are represented within squares at the bottom. The two vertical arrows, which lead from the conceptual variables to the measured variables, represent the operational definitions of the two variables. The arrows indicate the expectation that changes in the conceptual variables (psychotherapy and anxiety in this example) will cause changes in the corresponding measured variables. The measured variables are then used to draw inferences about the conceptual variables.
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Figure 2.1 Diagram of a Research Hypothesis
In this research hypothesis, the conceptual variable of attending psychotherapy is operationalized using the number of hours of psychotherapy the client has completed, and the conceptual variable of anxiety is operationalized using self-reported levels of anxiety. The research hypothesis is that more psychotherapy will be related to less reported anxiety.
Table 2.1 "Examples of the Operational Definitions of Conceptual Variables That Have Been Used in Psychological Research" lists some potential operational definitions of conceptual variables that have been used in psychological research. As you read through this list, note that in contrast to the abstract conceptual variables, the measured variables are very specific. This
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