Unit 0

Overconfidence:

People tend to overestimate their abilities and knowledge.

• Example: Thinking they are smarter, faster, stronger, more capable, aware, and observant than they really are.

Even when shown evidence that contradicts their beliefs, most say, “Well, I was close.”

Result: Sometimes people think we know more than we actually do.

Korean: Overconfidence는 우리가 실제 알고 있는 것 보다 더 많이 안다고 생각하는 것

Hindsight Bias:

The tendency to believe, after learning an outcome, that we would have foreseen it.

Known as the “I knew it all along” phenomenon.

Hindsight is 20/20: After an event, it’s easy to explain why it happened or why someone acted a certain way.

Psychological findings often seem like common sense because we observe human behavior, but scientific evidence is needed to support claims.

Korean: Hindsight Bias는 결과를 알게 된 후, 그 결과를 이미 알고 있었다고 예견할 수 있었다고 믿는 경향.

Scientific Method:

Scientists form hypotheses from theories, conduct research, and refine theories based on observations.

Theory: An explanation that organizes data and predicts observations. (Not a fact)

Hypothesis: A testable prediction, often implied by a theory. (Ask: “Can I test this?”)

Replication: Repeating a study to see if the findings hold true with the participants or situations.

Korean: 과학적 방법 (scientific method)는 이론에서 가설을 세움 - 연구 수행 - 연구 관철 결과를 바탕으로 이론 수정

• 이론(theory): 데이터를 정리하고 관찰을 예측할 수 있는 설명 (사실 아님)

• 가설(hypothesis): 테스트할 수 있는 예상. 보통 이론에서 나옴 (이 내용을 시험해볼 수 있을까?)는 느낌

• 재현(replication): 연구를 반복해서, 다른 사람이나 다른 상황에서도 같은 결과가 나오는지 확인

Descriptive Methods:

Case study, Survey and Naturalistic Observation record what happens, but does not explain why it happens (the cause)

Korean: 3가지의 것들은 무슨일이 일어났는지 관찰은 하지만 왜 일어났는지 설명하지는 못한다

Trust but Verify:

Falsifiability: the belief that for a hypothesis to be credible, it must be inherently disprovable.

• In other words, a hypothesis must be able to be tested and potentially proven wrong to be considered scientific.

Null Hypothesis:

• States that there is no relationship between the variables being studied.

• Serves as the testable statement in a falsifiable scenario.

Peer Review: a process before before a study is published where experts check the quality and validity of the research and ensure it contributes to the field.

Meta-Analysis: A method for statistically combining results from many studies.

• Estimates the effect size.

• Reviews multiple studies for common methods, results, or disagreements.

• Often done at the dissertation or graduate level to justify new research.

Korean: 믿되 확인하라

• Falsifiability: 가설이 과학적 이려면 틀릴 수도 있어야 한다

• 쉽게 말하면, “이 가설이 잘못될 수도 있지?” 라고 실험으로 확인할 수 있어야 한다는 것

• Null Hypothesis: 연구하는 변수들 사이에 관계가 없다고 말하는 가설 (과학 실험에서 테스트할 수 있는 기준 문장 역할)

• Peer Review: 연구가 출판되기 전에 다른 전문가들이 연구를 확인하는 과정 (연구의 질과 타당성을 체크하고, 그 분야에 실질적인 기여기 있는지 확인)

• Meta-Analysis: 여러 연구 결과를 통계적으로 합치는 과정 (효과 크기를 추정, 여러 연구에서 공통 방법, 결과, 또는 차이점을 검토) 보통 박사 과정이나 대학원 수준에서 새로운 연구 필요성을 정당화할 때 사용

Case Study:

Case Study: An observation technique were one person is studied in depth to try to reveal universal principles.

Pros:

• Provides insight into specific cases that cannot be studied ethically in larger groups.

Cons:

• Difficult to generalize findings to larger populations.

• Some events or circumstances cannot be replicated due to ethical issues.

Examples:

• Brain lesion studies

• Rare brain phenomena

• Socially isolated (“feral”) children

Korean: Case Study는 한 사람을 깊이 관찰해서 일반적으로 적용될 수 있는 원리를 찾는 방범.

• 장점은 윤리적으로 큰 집단에서 연구할 수 없는 경우, 특정 사례에 대한 깊은 통찰을 제공

• 단점은 결과를 많은 사람에게 일반화하기 어려움, 일부 사건이나 상황은 윤리 문제로 반복 실험 불가

• 예시: 뇌 손상 연구, 사회적으로 고립된 아이들

Survey:

Survey: a technique for ascertaining the self-reported attitudes or behaviors of people, usually by questioning representative, random sample.

Key Concepts:

• Representative Sample/Selection: Reflects the characteristics of the population.

• Random Sample/Selection: Every individual has an equal chance of being included.

• Generalization: The ability to apply results from the sample to the entire population.

• Link Scale: A rating scale used to measure a respondent’s attitude or opinion.

Pros:

• Can study large populations using a representative sample.

• Provides information on a broad range of topics.

• Less expensive than some other methods.

• Can be conducted relatively quickly.

• Example: Gallup polls, Kinsey report on sexuality

Cons:

1. Self-reporting is not always reliable

   • Self-report bias: Asking people about thoughts, feelings, or behaviors may be less accurate than direct measurement.

   • Social-desirability bias: Tendency to give answers that are socially approved, hiding true opinions.

   • Results depend on how questions are worded.

   • Provided answer choices may not reflect all possibilities.

2. Convenience sampling

   • Sample is chosen by chance or availability, no randomly or systematically

   • Example: Interviewing the first 50 people exiting a coffee shop, Petco, or Dollar Tree

   • Data cannot be generalized to the larger population → sampling bias

   • Example: Election poll interviewing only college graduates, survey excluding homeschooled adolescents

Korean: Survey(설문조사)는 사람들의 자기 보고식 태도나 행동을 알아보는 방법. (보통 대표적이고 무작위로 뽑은 샘플을 대상으로 질문)

• 대표 샘플: 모집단의 특성을 잘 반영하는 샘플

• 무작위 샘플: 모든 사람이 같은 확률로 포함될 기회를 가진 샘플

• 일반화: 샘플 결과를 젠체 모집단에 적용할 수 있는 능력

• 리커트 척도: 응답자의 태도나 의견을 측정하는 평가 척도

장점:

• 대표 샘플로 큰 집단 연구 가능, 다양한 정보 수집 가능, 빠르고 저렴

단점:

• 자기 보고 편향으로 생각/감정/행동 정확하지 않을 수 있음.

• 사회적 바람직 편향으로 보기 좋게 답하고 질문 wording에 따라 결과가 달라짐.

• 편의 샘플링으로 우연/접근성에 따라 샘플 선택으로 일반화 어려움(샘플링 편향).

예시:

• 갤럽 여론조사

• 킨지 보고서

Naturalistic Observation:

Definition: Observing and recording behavior in natural settings without trying to manipulate or control the situation.

Pros:

• Can observe people or animals in real, not artificial environments.

Cons:

• No control over events or variables.

Examples:

• Videotaping parenting in different cultures

• Recording students’ self seating patterns in the library

• Studying animal behavior in the wild

Methods of Observation:

• Tally counts: Nothing every time a behavior occurs

• Audio/video recordings

• Time sampling: Recording behaviors at different time intervals (random or systematic)

• Situation sampling: Observing a behavior in various situations/settings

Korean: Naturalistic Observation은 인위적으로 조작하지 않고 자연스러운 환경에서 행동을 관찰, 기록하는 방법

장점:

• 사람/동물을 현실적인 환경에서 관찰 가능

단점:

• 사건이나 변수 통제 불가

예시:

• 문화별 양육 방식 비디오 녹화

• 도서관에서 학생들이 자율적으로 앉는 패턴 기록

• 야생 동물 행동 연구

관찰 방법:

• 횟수 기록

• 오디오/비디오 녹화

• 시가 표집

• 상황 표집

Correlaional Methods:

Purpose: After describing phenomena, researchers examine wheather certain variables are related

Key point: When cariables appear to be related, they are said to

Korean: 목적은 형상을 기록한 후, 특정 변수들이 서로 관련이 있는지 확인. 핵심은 변수들이 서로 관련 있어 보이면, 이를 상관되어 있다(correlate)고 함

Correlation:

Definition: A measure of how much two variables change together, and how well one redicts the other.

Key Questions:

• How are two things related?

• How strong is this relationship?

• Can the relationship be use to make predictions?

Scatterplot

• A graph showing a cluser of dots, each representing two variables’ values.

• Less scatter = stronger correlation.

Korean: Correlation은 두 변수가 함께 얼마나 변하는지 측정 → 한 변수가 다른 변수를 얼마나 잘 예측할 수 있는지 보여줌

핵심질문:

• 두 변수는 어떻게 관련되어 있는가?

• 관계의 강도는 어느 정도인가?

• 이 관계로 예측이 가능한가?

Scatterplot

• 두 변수으 값을 점으로 표시한 그래프

• 점이 덜 흩어져 있을수록 → 상관관계가 강함

Types of Correlation:

Positive: two variables rise or fall together

Negative: two variables relate inversely to one another; as one rises, the other falls

No/Zero: two variables do not seem to be related

Correlation Coefficient:

Definition: A numerical measure of the strength of the linear relationship between two variables.

Purpose: Shows how well one variable predicts the other and how strong that prediction is.

Scale:

• r = 0 → No relationship

• r = + ___ → Positive correlation (as one increases, the other increases)

• r = - ___ → Negative correlation (as one increases, the other decreases)

Korean: Correlation Coefficient는 두 변수 간 선형 관계의 강도를 수치로 나타낸 것

• 의미: 한 변수가 다른 별수를 얼마나 잘 예측하는지 보여줌

Effect Size:

Definition: A measure of how meaningful the relationship between variables is, or how meaningful the differnece between groups is.

Purpose: Provides a quantitative measure of the magnitude of the effect.

Example:

• Turning on a lamp in a sunlit room → small effect

• Turning on a lamp in a dark room → large effect

Korean: Effect Size는 변수 간 간계나 집단 간 차이가 얼마나 의미 있는지를 보여주는 지표

• 목적은 효과의 크기를 수치화해서 표현함.

• 예시:

  • 햇빛이 들어오는 방에서 전등 켜기 → 작은 효과

  • 어두운 방에서 전등 켜기 → 큰 효과

Illusory Correlation:

Definition: The phenomenon of perceiving a relationship between variables (people, events, behaviors even when no actual relationship exist.

Example:

• Children’s wild behavior & moon phases

• Acy joints & weather changes

• Busy nights in the ER & moon phases

Korean: Illusory Correlation은 실제로는 관계가 없지만 변수들 사이에 관계가 있다고 착각하는 현상

Directionality Problem:

Definition: The situation where it is known that two variables are related, but it is not clear which is the cause and which is the effect (Correlation does not imply causation; you an’t tell the direction of the effect)

Korean: Directionality Problem은 두 변수가 관련이 있다는 것은 알지만, 어느 변수가 원인이고 어느 변수가 결과인지 알 수 없는 상황 (Correlation이 있다고 해서 Causation이 있다고 볼 수 없음)

Third Variable Problem:

Definition: Occurs when a third variable causes a mistaken causal relationship between two tother variables

Example:

• Correlation between ice cream sales and shark attacks

• Third vairable: warm weather → increases both ice cream sales and shark attacks

• Shark attacks ← (correlation) → ice cream sales

• Warm weather → (causation) → Shark attacks

• Warm weather → (causation) → Ice cream sales

Korean: Third Variable Problem은 두 변수 사이의 인과관계를 잘못 해석하게 만드는 세 번째 변수가 있을 때 발생

• 예시:

  • 아이스크림 판매량과 상어 공격 사이의 상관관계

  • 더운 날씨 → 아이스크림 판매와 상어 공격 둘 다 증가

Correlational Research:

Definition: Research that measures the exent of a relationship between two variables

Pros:

• Can quantify how strongly variables are related

Cons:

• Correlation does not imply causation → just because two things are realted does not mean one causes the other

• Cannot fully predict future behaviors or attitudes, even with a strong correlation coefficient

• Be aware of Directionality Problem and Third Variable Problem

Korean: Correlational Research는 두 변수 간 관계의 정도를 측정하는 연구

장점:

• 변수들 간 연관성의 강도를 수치화 가능

단점:

• Correlation은 Causation이 아님. 관련 있다고 해서 한 변수가 다른 변수를 일으킨다는 뜻은 아님

• 강한 Correlation에도 미래 행동/태도 완전 예측 불가

• Direactionality Problem와 Third Variable Problem 주의해야 함

Experimental Methods:

Purpose: To establish cause and effect by isolating and controlling variables

Reason: Everyday behaviors and attitudes are influenced by many factors, so experiments are needed to determine which factor actually causes a change

Korean: 변수를 통제하고 격리하여 원인과 결과를 확인. 이유로는 일상 행동과 태도는 많은 요인에 영향을 받기 때문에, 어떤 요인이 실제 변화를 일으키는지 확인하려면 실험이 필요.

Experiment:

Definition: A research method where an investigator manipulates one or more factors to observe the effect on a behavior or mental process.

Key features:

• Manipulate the factor(s) of influence

• Hold other variables constant

• Randomly assign participants to groups

Purpose: Unlike correlational studies that oberve natural relationships, experiments actively manipulate a factor to determine its causal effect.

Korean: Experiment(실험)이란 연구자가 한 가지 이상의 요인을 의도적으로 조작하여 그것이 행동이나 정신 과정에 어떤 영향을 주는지 관찰하는 방법

핵심특징:

• 요인을 조작하다

• 다른 변할 수 있는 요인은 통제한다

• 참가자를 무작위로 배정한다

목적: Correlational research가 자연스러운 관계를 밝히는 것과 달리, Experiment는 variable을 직접 조작하여 원인과 결과를 밝혀내다

Variable:

Definition: Aything that can change or be changed within an experiment

Independent Variable (IV)

• the variable being manipulated

  • the effect of the IV is the forcus of the study

Dependent Variable (DV)

• the outcome being studied as a result of/response to the IV

  • usually a behavior/mental process

TIP!!

• “IF the IV, THEN the DV.”

Korean: Variable(변수)는 실험에서 바꿀 수 있거나 바뀔 수 있는 모든 것

Independent Variable (IV)

• 직접 조작하는 변수

• 무엇이 영향을 주는가에 해당

• 예: 약을 먹었는지 안 먹었는지

Dependent Variable (DV)

• IV에 영향을 받아서 결과로 나타나는 변수

• 무엇이 영향을 받는가에 해당

• 예: 약을 먹은 후 환자의 증상이 얼마나 나이졌는지

쉽게 말하면:

• IV = 원인

• DV = 결과

Operational Definition:

Definition: Specific and measurable definition of the IV and DV

• taking a vague and unspecified variable and making it clear and precise

Korean: Operational Definiton은 IV와 DV를 좀 더 specific하게 explain하는 것

Grouping in Research:

• Experimental Group: participants exposed to the IV

• Control Group: participants not exposed to the IV; used for comparison

Key point:

• Control groups help determine the true effect of the IV

• There can be more than one experimental or control group depending on the study design

Example:

• Experimental Group: takes the real drug

• Control Group: takes a placeo (fake pill)

Korean:

• Experimental Group

  • IV의 영향을 받는 집단

  • 즉, 처치(treatment)를 받은 그룹

• Control Group

  • IV의 영향을 받지 않는 집단

  • 비교 기준 역할

• 핵심 포인트

  • Control Group이 있어야 IV의 진짜 효과를 알 수 있음

  • 하나 이상의 Experimental Group & Control Group 가능 → 상황에 따라 여러 조건 비교 가능

How Are Groups Created?:

• Random Assignment: each paticipant has an equal chance of being placed into any group (experimental or control)

• Purpose: ensure groups are similar at the start, reducing bias and making results more reliable

Example:

• Flip a coin → Heads = experimental group, Tail = control group

Korean: 그룹은 무작위으로 공평성을 위해 배정

Placebo:

Definition: a substance or treatment that has no effect apart from a person’s belief in it

• Placebo effect: a person receiving the placebo may report positive effects due to a belief in the drug/treatment

• Single blind procedure: participants do not know if they are in the experimental or control group

• Double blind procedure: participants nor researchers know who is in the experimental or control group

  • Reduces experimenter bias: occurs when scientist unconsciously influence results to support a desired outcome. But andom assignment reduces experimenter bias by making groups similar and preventing favoritism or unconscious influence

Korean: 플라시보 효과는 실제로는 효과가 없지만 사람들이 긍정적으로 있다고 믿는 것

• Single blind procedure은 참가자 자신이 experimental group인지 control group인지 모름

• Double blind precedure은 참가자와 연구자 모두 누가 experimental group이고 control group인지 모름

• Reduces experimenter bias는 연구자가 무의식적으로 원하는 결과가 나오도록 연구 결과에 영향을 주는 경우. 무작위 배정을 사용하면 그루ㅂ이 비슷하게 되어, 실험자가 결과에 영향을 미칠 가능성을 줄일 수 있음

Confounding Variables:

Definition: a third variable that influences both the IV and DV

Korean: Confounding Variables는 IV랑 DV 둘 다 influence하는 variable

What kinds of measures did we use?:

Quanlitative Measures: collecting and evaluating non-numerical data(not like a number data) in order to understand concepts or opinions (body language, recording behaviors like dialoue, etc.)

Quantitative Measures: collecting and evaluating numerical date (exact number data)

Korean: Quanlitative Measures는 숫자가 아닌 몸이나 말로 생각을 이해하는 것, Quantitave Measures는 숫자로 data를 수집

Comparing Research Methods:

1. Descriptive(설명)

   • Purpose: to observe and record behavior

   • Procedure: case study, survey, naturalistic observation

   • Cons:

     • no control over variables

     • Stingle uniques situations can be misleading

     • Does not provide cause and effect

2. Correlational(상관?)

   • Prupose:

     • to detect naturally occurring relationships

     • To assess how well one variable predicts another

   • Procedure: computing statistical relationships between data points

   • Cons: does not provide cause and effect

3. Experimental(실험)

   • Purpose: to explore cause and effect

   • Procedure:

     • manipulate one or more factore

     • random assignment to groups

   • Can manipulate IV

   • Cons:

     • sometimes not possible

     • results may not generalize to toer contexts

Federal Ethics Regulations:

• Purpose: Ensure research follows ethical guidelines

Key committes:

1. Institutional Review Board (IRB)

   • Reviews human research for ethical violations

2. Institutional Animal Care & Use committee (IACUC)

   • Reviews animal research for ethical violations

Humans in Research (APA Guidelines):

1. Informed Consent / Assent

   • Obtain permission from each participant.

   • Informed consent: participants get info about the study, risks, and decide to participate.

   • Informed assent: minors or those who can’t consent can participate if parent/legal guardian agrees.

   • Participants can stop anytime without consequences.

   • Deception is allowed if necessary; must explain true purpose during debriefing.

   • Confederates: experimenter’s assistants posing as participants to observe natural reactions.

2. Protection from Harm

   • Participants must be protected from physical and emotional harm.

   • Temporary stress or deception is allowed only if essential and benefits → risks.

3. Confidentiality & Anonymity

   • Participants’ identities must be kept private.

4. Debriefing

   • Explain what was done and why after the study.

Frequency Distribution:

• a list or display of data on a scale of measurement; goal is to simplify the organization an presentation of data

• Normal curve: a distibution where the mean, median and mode are equal