methods in psychology Flashcards
What is the difference between dogmatist and empiricist?
dogmatists: thought best way to understand illness was to develop theories about the body
empiricists: though best way was to examine sick people
Why didn’t the rivalry between dogmatists and empiricists last long?
Because people who went to see dogmatists tended to die
Define empiricism
belief that accurate knowledge about the world can be gained by observing it
What is the backbone of the scientific method ?
Empiricism
define scientific method
- a procedure fore using empirical evidence to establish facts
- only way to learn the truth about the world is:
1.develop a theory
2. derive falsifiable hypothesis from it
3. test hypothesis by observing the world
What are explanations of natural phenomena or ideas about how something works?
- theories
- a good theory makes specific predictions about what we should observe in the world if the theory is true
- a theory can never be proved right
Define hypothesis
a falsifiable prediction made by a theory
What does testing hypothesis require?
- empirical method: a set of rules and techniques for observation
What are the 3 qualities that make humans difficult to study compared to inanimate things?
- people are very complex
- people are very variable (no 2 people say, think or feel the same under exact same circumstances)
- people are very reactive (people act differently when they think they are being observed)
How have psychologists met the challenge of studying humans given their complexity, variability and reactivity ?
Developed 2 methods:
- methods of observation: allows them to discover what people do
- methods of explanation: allows them to discover why people do it
Why are everyday observations not good enough for scientific study?
- everyday observations are often inconsistent
- everyday observations are often incomplete
What must you do before measuring anything?
- define the property we want to measure
- find a way to detect it by finding and instrument/device that can detect our property as we defined it
What is an operational definition?
description of a property in measurable terms
What is one of the key features of a good operational definition?
construct validity: feature of Op.Defs. whose specified conditions are generally considered good indicators of the specified property
What are the 2 key features of a good detector?
power: detector’s ability to detect the presence of differences or changes in the magnitude of a property
reliability: detector’s ability to detect the absence of differences or changes in the magnitude of a property
Define demand characteristics
- those aspects of an observational setting that cause people to behave as they think someone else wants/expects
- when humans know they are being observed they will often try to behave as they think the observer wants or expects them to behave
What are the 3 ways we can avoid demand characteristics?
- naturalistic observation
- privacy and control
- unawareness
How does naturalistic observation avoid demand characteristics?
- a technique for gathering information by unobtrusively observing people in their natural environment
- not always practical: some events just don’t occur naturally
- some things can only be observed through direct interaction with people
How does Privacy and control avoid demand characteristics?
- allowing participants in their study to respond anonymously
- measuring behaviors that are not under a person’s voluntary control
How does unawareness avoid demand characteristics?
- make sure that the people who are being observed are unaware of the true purpose of the observation
- psychologists may mislead people by telling them they are studying one thing when they are studying another
Define observer bias
the tendency for observer’s expectations to influence both what they believe they observed and what they actually observed
What is the most commonly used technique to avoid observer bias?
double-blind study: study in which neither the participant nor the researcher knows how the participants are expected to behave
Define population
a complete collection of people
Define sample
a partial collection of people drawn from a population
What are 2 techniques used for making sense of big spreadsheets of numbers?
graphic representations and descriptive statistics
What is the most common kind of graphic representation?
frequency distribution: graphic representation showing the number of times that a measurement of a property takes on each of its possible values
- can be negatively, positively skewed and symmetrical
Define normal distribution
mathematically defines distribution in which the frequency of measurements is highest in the middle and decreases symmetrically in both directions
What are descriptive stats in psychology?
- Brief summary statements that capture the essential information from a frequency distribution
What are the 2 most common types of descriptive stats?
- Description of central tendency: statements about the value of measurements that tend to lie near Centre of frequency distribution
- description of variability: statements about the extent to which measurements in a frequency distribution differ from each other
What are the 3 common descriptions of central tendency?
mode: value of the most frequently observed measurement
median: average value of all measur.
mean: value in the middle
What is the simplest measure of variability?
range: the value of the largest measurement in a frequency distribution minus the value of the smallest measurement
Define standard deviation
- how each of the measurements in a frequency distribution differ from the mean
- an estimate of how far on average the various measurements are from the centre of the distribution
Define correlation
- relationship btw variables in which variations in the value of one of the variables are synchronized with variations in the value off the other
- when patterns of variation are synchronized 2 variables are correlated
How do statisticians estimate how accurate predictions based on correlation are?
- by measuring the direction and strength of correlation
- direction: either positive or negative
What is a positive correlation?
When 2 variables have a more-is-more relationship
What is a negative correlation?
When 2 variables have a more-is-less relationship
What is the correlation coefficient?
- mathematical measure of both the direction an strength of a correlation
- symbolized by letter r: value ranges only from -1 to 1
Define variable
properties that can have more than one value
Define natural correlation
correlation that is observed in the natural world
cannot tell us whether they have a causal relationship
What is the third variable problem?
the natural correlation between two variables can’t be taken as evidence of a causal relationship between them, because a third variable might be causing them both
What technique can help establish causation btw two variables?
- Experimentation
- 2 steps: manipulation and random assignment
Define manipulation in an experiment?
- technique for determining the causal power of a variable by actively changing its value
- experiments require to change one variable’s value, measure the other then compare
What is the variable that is manipulated in an experiment called?
the independent variable: value determined by the experimenter
Define Measuring in an experiment
- variable that is measured in an experiment is the dependent variable
- value depends on the value of the independent variable
Define comparing in an experiment
compare the value of the dependent variable in one condition with the value of the dependent variable in the other
Define self-selection
problem that occurs when anything about a participants determines the value of the independent variable to which the participant was exposed
Define random assignment
procedure that assigns participants to conditions by chance
When does an experiment have internal validity?
- when it establishes a causal relationship between 2 variables
- everything inside the experiment is working exactly as it should for us to use results to draw conclusions about causal relationship btw the independent and dependent variables
Why does the operational definition of variables matter in an experiment?
- results of an experiment depend on how the independent and dependent variables are op. defined
- we should thus operationally define variables as they are defined in the real world
- this leads to external validity
define external validity
an experiment in which variables have been operationally defined in a representative way
Must all experiments be externally valid?
- no, many aren’t
- experiments aren’t usually meant to be miniature versions of everyday life > their lack of external validity is not necessarily a problem
define a case method
procedure for gathering scientific information by studying a single individual
Define random sampling
- technique for selecting participants that ensures that every member of a population has an equal chance of being included in the sample
- sample is said to representative of the population
- allows us to generalize from the sample to the pop.
Define replication
an experiment that uses the same procedures as a previous experiment but with a new sample from the same population
What are the 2 types of errors researchers can make when drawing conclusions from evidence?
- Type 1 error: when they conclude there is a causal relationship between two variables when there isn’t one >fluke
- Type 2 error: when they conclude there is no causal relationship when there is one > flunk
who invented the scientific method ?
- 1620: Francis bacon
- previously known as Baconian method
What does empirical evidence require?
Critical thinking
What are 2 natural human tendencies according to Francis Bacon?
- tendency to see what we expect or want to see
- tendency to ignore what we can’t see
- our beliefs colour our view of new evidence, causing us to see what we expect to see > evidence often seems to confirm what we believed all along
What colours our view of evidence?
beliefs, preferences, prejudices , ambitions, aversions, etc.
In what 2 ways do our beliefs and desires shape our view of evidence?
- when evidence confirms what we believe we ask ourselves “Can i believe this” when evidence disconfirms what we believe we ask ourselves “must I believe this”
- our beliefs and desires influence which evidence we even consider in the first place/ studies show that people prefer to search for evidence that confirms their beliefs and fulfills their desires
What are the 2 rules of critical thinking?
- Doubt your own conclusions: scientists expose share their work with peers who they know will disagree
- Consider what you don’t see: tendency to ignore missing evidence can lead us to erroneous conclusions
Why were the Nuremberg Code of 1947 and Declaration of Helsinki developed?
During WW2 Nazis performed inhumane experiments on human subjects which appalled the international community.
After end of war they created guidelines for ethical treatment of experiment participants
What is the Tri-Council Policy statement? (TCPS)
- agencies that cover all research involving human persons or tissue in Canada
- core principles:
respect for persons: right to decisions w/o coercion
concern for welfare: attempt to maximise benefits and reduce risks to participant
just: distribute benefits and risks equally to all participants w/o prejudice
What are the most important ethical rules that govern the practice of psych research?
- Informed consent
- freedom from coercion
- protection from harm
- risk-benefit analysis
- deception
- debriefing
- confidentiality
Who enforces rules that psychologists must follow in research?
- institutions have Research Ethics Boards (REBs)
- psychologists may only conduct research once it has been reviewed and approved by REB
Which agency is responsible for establishing standards for the ethical use and care for animals in research in Canada?
- Canadian Council on Animal care
- 3 Rs
Replacement: researchers must prove there is no alternative to using animals and their use is justified by scientific value of study
Reduction: researchers must use the smallest number of animals possible to achieve research
Refinement: procedures must be modified to minimize discomfort, infection, illness, and pain
How does the Honor system in psychological research work?
- science is a community enterprise
- when publishing reports of their studies psychologist are required to be truthful > can’t fabricate results
- psychologists required to share credit fairly by including co-authors and contributors
- psychologists are obligated to share their data
- the fact that anyone can check on anyone else makes honor system effective
