unit 0 - an introduction to science practices: research methods and data interpretation

psychology

• the science of behavior and mental processes

• it seeks to answer questions about us all

  • how and why we think, feel, and act as we do?

• it uses research and interpretation of the resulting data to separate uninformed opinions from examined conclusions

  • facts of psychology comes from scientifically derived evidence

curiosity

• willingness to explore and ask questions

  • does it work? when put to the test, can its predictions be confirmed?

skepticism

• questioning ideas and requiring evidence

  • what do you mean? how do you know

• differentiating reality from fantasy requires a healthy skepticism

  • an attitude that is not cynical (doubt), but also not gullible (believing)

humility

• being open to being wrong and accepting new perspectives

  • that was unexpected, let’s explore further!

• researchers must be willing researchers must be willing to be surprised and follow new ideas

  • people and animals do not always behave as predicted“

• the rat is always right”

  • motto/belief that data is more important than opinions

critical thinking

• thinking that examines assumptions, appraises the source, discerns hidden biases, evaluates evidence, and assesses conclusions

  • a type of smart thinking that stems from the scientific attitude

• critical thinking asks questions: “what is the evidence?”

  • they dislike when people make factual claims based on their gut

• such beliefs (mislabeled as feelings) may or may not be true

hindsight bias

• i-knew-it-all-along phenomenon

  • the tendency to believe, after learning an outcome, that one would have foreseen it

• can be demonstrated by giving half of the members some purported psychological finding and giving the other half the opposite

  • those given this untrue result can easily imagine it, and most will see it as unsurprising

• such errors in people’s recollections and explanations show why we need research

  • common sense describes, after the fact, what has happened better than predicting what will

overconfidence

• we humans tend to think we know more than we do

• asked how sure we are of our answers to factual questions, we tend to be more confident than correct

  • our confidence drives us to quick, rather than correct, thinking and answers

• psychologist philip tetlock collected more than 27,000 expert predictions on world events

  • these predictions, which experts made with 80$ confidence on average, were right less than 40% of the time

  • only 2% of people excel at predicting social behavior

    • “superforecasters” avoid overconfidence

    • they gather facts, balance arguments, and make a choice

perceiving order in random events

• humans are born with an eagerness to make sense of our world

• in random data, we often find patterns because random sequences often to not look random

  • in actual randomness, patterns and streaks (repeating digits) occur more than people expect

  • that is why people find it hard to generate random-like sequences

• why are we so prone to pattern seeking?

  • a random, unpredictable world in unsettling

  • making sense of our world relieves stress and helps us get on with daily living

the scientific method

• a self-correcting process for evaluating ideas with observation and analysis

• test hunches and plausible-sounding theories

  • if a theory works (the data support its predictions), good!

  • if the predictions fail, the theory gets revised or rejected

• when researchers submit their work to a scientific journal, the journal editor uses peer reviews to determine if it gets published

peer reviewers

• scientific experts who evaluate a research article’s theory, originality, and accuracy

theory

• an explanation using an integrated set of principles that organizes observations and predicts behavior or events

hypothesis

• testable predictions, often implied by a theory

  • such predictions specify which results would support the theory and which results would disconfirm it

falsifiability

• the possibility that an idea, hypothesis, or theory can be disproven by an observation or an experiment

  • our theories can bias our observations

operational definiton

• a carefully worded statement of the exact operations used in a research study

  • as a check on our own biases, psychologists report their research with operational definitions of procedures and concepts

replication

• repeating the essence of a research study, usually with different circumstances, to see whether the basic findings can be reproduced

case-study

• non-experimental technique in which one individual or group is studied in depth in the hope of revealing universal principles

  • they can inspire theories and can often suggest directions for further study, but they are not always generalizable and can be misleading

  • ex. sigmund freud’s case study of a 5-year-old han’s extreme fear of horses led Freud to his theory of childhood sexuality

    • he believed that hans felt desire for his mother, feared castration by his father, and transferred this into phobia

naturalistic observations

• non-experimental technique of observing and recording behavior in naturally occurring situations without trying to manipulate and control the situation

  • ex. a research team studied the ups and downs of human moods by counting positive and negative worlds in 504 million tweets around the world

    • it showed that saturday nights to be the most positive and tuesday afternoons to be the most negative

surveys 

• non-experimental technique for obtaining the self-reported attitudes or behaviors of a particular group, usually by questioning a representative (random sample)

  • small changes in wording or phrasing can make a big difference

social desirability bias

• people answering in a way they think will please the researcher

self-report bias

• when people do not accurately report or remember their behaviors

random sample

• a sample that fairly represents a population because each member has an equal chance of inclusion

population

• all those in a group being studied, from which random samples may be drawn

sampling bias

• a flawed sampling process that produces an unrepresentative sample

correlation

• a measure of the extent to which two factors vary together, and thus of how well either factor predicts the other

  • asks how strongly how two variables are related

• correlation does not equal causation

  • correlation suggests a possible cause-effect relationship but does not prove it

  • correlation research has a directionally problem and third variable problem

• correlations make clear the relationships we may otherwise miss and also keep us from falsely assuming a relationship exists when there is none

correlation coefficient

• a statistical index of the relationship between two variables from -1.00 to +1.00

variable

• anything that can vary and is feasible and ethical to measure

scatter plots

• a graphed cluster of dots that show patterns (relationship and strength) or correlation (r)

  • positive correlation (r = +1.00 to 0.00): when scores for one variable increase in direct proposition to scores for another variable

  • no correlation (r = 0.00): no relationship

  • negative correlation (r = 0.00 to -1.00): when scores for one variable decrease precisely as scores for another variable rises

directionality problem

• cannot tell us which variable is the cause and which one is the effect

third variable problem

• has 3+ variables

illusory correlation

• perceiving a relationship where non exists, or perceiving a stronger-than-actual relationship

  • they can feed an illusion of control, that we can personally influence chance events

regression toward the mean

• a statistical phenomenon in which the tendency for extreme or unusual scores or events to fall back (regress) toward the average

  • extreme results are often due to unfortunate or extremely fortunate combinations that will likely may not happen again

  • failure to recognize regression can cause superstitious thinking

experiment

• a research method in which enables researchers to isolate the effects of one or more factors by manipulating the factors of interest and holding constant other factors

• experimental manipulation:

  • experiments are used to determine and identify cause and effect

experimental group

• the group exposed to the treatment (one version of the independent variable)

control group

• the group not exposed to the treatment to serve as a comparison for evaluating the effort of the treatment

random assignment

• assigning participants to experimental and control groups by chance, thus minimizing the preexisting differences between the two groups (equalizes)

  • thus, if the groups differ at the end, we can surmise that the treatment had an effect

single-blind procedure

• an experimental procedure in which the research participants are ignorant (blind) about whether they have received a treatment or a placebo (fake treatment)

double-blind procedure

• an experimental procedure in which both the research participants and the research staff are ignorant about whether the research participants have received the treatment or the placebo (used in most drug-evaluation studies)

placebo effect

• when a person experiences improvement in their condition after receiving a fake treatment

  • to know how effective a therapy is, researchers must control for a possible placebo effect

independent variable

• the factor that is manipulated in an experiment; the variable whose effect is being studied

confounding variable

• a factor other than the factor being studied that may influence a study’s results

  • random assignment controls for confounding variables

experimenter bias

• when researchers may unintentionally influence results to confirm their own beliefs

dependent variable

• the outcome that is measured, the variable that may change when the independent variable is manipulated

validity

• the extent to which a test or experiment measures or predicts what it is supposed to

• key goal of experiments

quantitative research

• a research method that relies on quantifiable, numerical data

qualitative research

• a research method that relied on in-depth, narrative data that are not translated into numbers

animal ethics

• british psychological society (BPS) – animals must be housed in natural conditions

• american psychological association (APA) – researchers must provide humane care and minimize discomfort

• EU parliament – mandates standards for care and housing

human ethics

• researchers must obtain potential participants’ informed consent (assent for minors) to take part

• researchers must protect participants from greater-than-usual harm and discomfort

  • most psychological studies are free of stress

  • some studies may use temporary stress or deception (only when justifiable by scientific value)

• researchers must keep information about each individual participant confidential

• researchers must fully debrief people

confederates

• someone who participates in a research study, but is actively working for the researcher and is aware of the true purpose of the experiment

informed consent

• giving potential participants enough information about a study to enable them to choose whether they want to participate or not

debrief

• the post experimental explanation of a study, including its purpose and any deceptions, to its participants

institutional review boards (IRBs)

• enforces ethical codes at universities and research organizations

• comprised of at least 5 people that must include one scientist, one non-scientist, and one community member

values in psychology

• values affect what we study, how we study it, and how we interpret results

• psychology’s power to persuade can be used for good or evil

• psychology’s purpose is to enlighten and in service humanity by addressing global changes and personal struggles

descriptive statistics

• numerical data used to measure and describe characteristics of groups

• includes measures of central tendency and measures of variation

histogram

• a bar graph depicting a frequency distribution

measures of central tendency

• a single score that represents a whole set of scores

  • mode

  • mean

  • median

• measures of central tendency neatly summarize data, but sometimes the distribution may be lopsided

  • the mode, mean, and median can provide different true facts or information about a distribution

mode

• the most frequently occurring score(s) in a distribution

bimodal distribution

• occurs when there are two frequently occurring scores

mean

• the arithmetic average of a distribution, obtained by adding the scores and then dividing it by the number of scores

median

• the middle score in a distribution

  • 50th percentile

  • half of the scores are above it, half are below it

percentile rank

• the percentage of scores that are lower than a given score

skewed distribution

• a representation of scores that lack symmetry about their average value

measures of variation

• how similar or diverse the scores are

  • range

  • standard deviation

range

• the difference between the highest and lowest scores in a distribution

standard deviation

• a computed measure of how much scores vary around the mean score

  • it is best a gauging whether each scores are packed together or dispersed because it incorporates information from each score

normal curve

• a symmetrical bell-shaped curve that describes the distribution of many types of data

  • large numbers of data often form a symmetrical, bell-shaped distribution

• most scores fall near the mean

  • 68% - within one standard deviation

  • 95% - within two standard deviations

  • 99.7% - within three standard deviations

inferential statistics

• numerical data that allow one to generalize or infer from the sample data the probability of something being true of a population

  • helps determine if results can be generalized to a larger population (all those in a group being studied)

  • it includes ways of determining the reliability and significance of an observed difference between results for different groups

meta-analysis

• a statistical procedure for analysing the results of multiple studies for reach a conclusion

  • it is better to conduct multiple studies and combine all the estimates than using just one that only gives on brief peek at what is going on in the population

statistical significance

• a statistical statement of how likely that a result occurred by chance, assuming there is no difference between populations being studied

• occurs when estimates are precise and there is a large difference

  • means that the observed difference is more than just chance variation

• “statistically significant” results may have little practical significance

  • when a sample is large, a result may be statistically significant but have a tiny effect size

null hypothesis

• assumption that no difference exists

  • if a large difference exists, they reject it and support an alternative hypothesis

p-values

• indicates the probability of the result, given the null hypothesis

  • evidence that we can reject the null occurs when the probability (p-value) of that result is very low (p < 0.05)

effect size

• the strength of the relationship between two variables

confidence interval

• a range of values that likely includes the population’s true mean value

  • helps researchers estimate whether a sample’s range of scores likely includes the population’s true mean value

philosophy

• the study of the fundamental nature of knowledge and reality

  • what is truth?

  • what is real?

  • how do we know what we know?

  • what is knowledge

physiology

• the branch of biology that studies the way a living organism’s body function

  • how do cells in the brain communicate?

  • how do hormones work?

  • how do the different divisions of the nervous system work together?

empiricism

• the idea that knowledge comes from experience, and that observation and experimentation allow us to gain scientific knowledge

  • in modern psychology, we rely on empirical research to understand human thought and behavior

psychoanalytic perspective

• sigmund freud

  • australian neurologist

  • believed psychological illness was different than physical illness and could be cured with “talking therapy”

  • founder of psychoanalysis

• approach

  • first approach developed outside of a university setting

  • focused on the cause, development, and treatment of abnormal behavior

  • emphasised the role of the unconscious mind

    • the memories, feelings, and drives that are outside of our awareness

  • believed that early childhood experiences influence personality and behavior and that we are driven primarily by unconscious desires and feelings

  • criticized as being unscientific since the unconscious mind cannot be studied objectively

psychodynamic perspective

• a modernized version of the psychoanalytic perspective

• moved away from some of freud’s more controversial ideas

behaviorist perspective

• believed psychology should only focus on what could be objectively observed and measured

• redefined psychology as the scientific study of observable behavior

• watson conducted infamous little albert experiment

• not concerned with things that cannot be directly observed, such as thoughts, feelings, and the unconscious mind

• believes behavior is learned

  • conditioned by environmental factors

• focuses on how behaviors are learned and modified

cognitive perspective

• studies how thinking and perception influence behavior

  • how we direct our attention

  • memory

  • thinking

  • problem solving

  • decision making

• in the cognitive view, an individual’s mental processes are in control of behavior through memories, perceptions, images, and thinking

cognition

• thinking and information processing

humanistic perspective

• addressed perceived flaws in both the psychoanalytic and behavioral approaches

• focuses on people’s potential and their drive to be their best

• has a more positive outlook on people than the behavioral or psychoanalytic approaches

• emphasizes a person’s positive qualities, the capacity for human growth or reaching one’s potential, and the freedom to choose one’s destiny

• self-actualization

self-actualization

• the psychological need to fulfill one's fullest potential, characterized by continuous personal growth, creativity, and self-fulfillment

sociocultural perspective

• emphasizes the impact of people’s culture, religion, ethnicity, gender, income level, and overall environment on a person’s thinking and behavior

• compares behavior across countries and within ethnic and cultural groups

biological perspective

• focuses on how genetics, the nervous system, hormones, and brain structures influence a person’s thinking and behavior

• is concerned with the biological causes of human thought and behavior and is interested in how biological treatments may improve certain psychological conditions

neuroscience

• the study of the brain and nervous system

evolutionary perspective

• began with charles darwin

• emphasizes how evolution influences thinking and behavior

  • looks for aspects of human thought and behavior that help us and our genes survive over time

• focuses on humans as a species, not as specific individuals

biopsychosocial perspective

• emphasizes that biological, psychological, and social forces all influence behavior

• no person or behavior can be explained by one perspective alone

• the approach that best helps us understand human thought and behavior

• helps us confront psychology's most persistent issue: nature vs. nurture

nature vs. nurture

• the controversy over how much our psychological traits and behaviors can be explained by genes (nature) and how much can be explained by experience (nurture)

psychiatrist

• medical doctor specializing in the diagnosis and treatment of mental illness

• typically prescribes medication to treat mental illness

• works in hospitals, clinics, rehabilitation centers, and private practices

clinical psychologist

• psychologist who specializes in the diagnosis and treatment of mental disorders

• provides counseling and therapy

• does not prescribe medication

• works in hospitals, clinics, rehabilitation centers, and private practices

counseling psychologist

• assists people with personal problems

  • often related to school, work, relationships, etc

• provides counseling and therapy

• most commonly works in private practice or clinics

cognitive neuroscientist

• studies the biological processes that enable cognition

  • brain structures

  • neural networks

school psychologist

• tests students for learning and emotional struggles

• helps create individualized education plans for students with learning and emotional struggles

• occasionally provides counselling, but not often

educational psychologist

• researches how people learn and remember information

• helps develop more effective curriculum, testing procedures, classroom structures, etc

• does not focus on individual students like a school psychologist

developmental psychologist

• studies how people change and develop over their lifespan

  • cognitive and motor development, language acquisition, emotional development

personality psychologist

• studies people’s characteristic patterns of thinking, feeling, and acting

social psychologist

• studies how we think about, influence, and relate to other people

experimental psychologist

• using experiments to study human thought and behavior

applied research

• esearch that is undertaken to solve a particular problem, not just to learn something new

industrial/organizational psychology (I/O)

• uses psychological training in workplace settings

• helps companies select and train employees, boost morale and productivity, design products, and implement systems