Studies, Variability, Design Flashcards
What are ways to acquire knowledge?
Authority, personal experience, the use of reason (logic), empiricism, science
What is the method of agreement?
if X then Y, experimental group
What is the method of disagreement?
if not X then not Y, control group
What are the principles of science?
Empiricism, objectivity, skepticism, openness, tentativeness, anti-authoritarianism
What is empiricism?
Evidence about reality or for theory must be: OBJECTIVE, observable, capable of being checked and verified by others
What is openness?
Can be repeated, verifiability via replication
What is tentativeness?
Current scientific explanation are only provisional, can change, new and better theories can replace
What is anti-authoritarianism
Only those theories that can be supported by empirical evidence are accepted by science and even then acceptance is tentative and open to modification in light of new evidence
What are the goals of science?
Describe, explain, predict, control
What are the stages in a psychological research in order?
Theory - prediction/ hypothesis - design a study - data 1. summarise: organise, explore, display, summarise 2. analysis: statistics tests (back to theory) - write a report - repeated experiments (back to data) - theory confirmed
What does a prediction have to be? And where is it best tested?
Has to be precise, concrete and observable and is best tested in experiments
What is a fundamental scientific controversy?
A disagreement about a central hypothesis or theory
What is a secondary scientific controversy?
A disagreement about less central aspects of a scientific idea and outcome of this does not impact the validity of the overall theory
What makes a good theory?
That they are falsifiable, not circular, do not contain scientific ideas, contain precise definitions of the associated terms and concepts
What is the scientific process?
Theory > hypotheses > design a study > data - describe, - analyse (revise theory if needed) > write a report > repeated experiments (not supported back to data) > theory confirmed
Ethically, what are some risks to participants?
Physical harm, psychological stress and loss of privacy.
What is the independent variable?
The variable independently manipulated by the experimenter
In a quasi-experiment what is the independent variable?
The variable used to categorise participants, measured by the experimenter
What is the dependent variable?
Is a measure of some tribute or behaviour resulting from changes in the IV. It is dependent on the IV
What is the null hypothesis?
No relationship between the IV and DV, results due to chance, ‘boring’
What is the alternate hypothesis?
There is a relationship between IV and Dv, ‘real’
What is an operational definition?
A specification on how to measure a variable
What are some examples of extraneous variables?
Individual differences like IQ and situational variables like noise, time of day and temperature
What is a perk of random variability?
It tends to obscure the effect of the IV on the DV
What is a confounding variable?
A variable that changes systematically with IV. It ruins the experiment because you can’t be sure which variable caused the changes in the DV
By accepting that your current hypothesis may need to be revised or discarded in light of future observations, you are demonstrating the scientific principle of what?
Tentativeness
Situational variables can be dealt with by doing what?
Holding them constant, balancing them across conditions and allowing them to vary at random
Why is random assignment good?
It equalises the groups before any manipulation is applied, eliminates systematic differences between the groups, in that age, IQ (etc.) are randomly distributed over both groups
Experimental research advantage is that it can make casual claims about relationships however what are some disadvantages?
Not many volunteers (ethical concerns), random allocation is impossible at times
What is a key part of quasi-experiments?
They have specific groups
Counterbalancing is a procedure employed in which type of research design?
Repeated measures
What is an issue for repeated measures?
carry over effects
What is independent groups design?
Participants are randomly assigned to one of the experimental conditions. This balances individual differences.
What are observational studies?
Quasi-experimental and correlational
What is a good control group?
Experiences everything the experimental group experiences except the critical value of the IV therefore, any differences can be attributed to IV
What are three important characteristics of a scientific theory?
It summarises existing knowledge in a given area, it provides a tentative explanation for the phenomenon, it serves as a basis for predictions to be tested
For a theory to qualify as scientific it must be what?
falsifiable
What is the main difference between experimental and observational research?
The IV is manipulated and controlled
What is the specific aims of research design?
To eliminate confounding variables and to minimise random variability
The distance from a golfer’s tee would constitute what?
Ratio scaling
What are examples of quantitative and qualitative measurements?
quantitative: height, weight. qualitative: gender, eye colour
What are the types of measurement variables?
Discrete - no intermediate values exist (number of chess pieces lost in a match), dichotomous - discrete variable with only two possible values (female or male), continuous - infinite number of values
What information is provided for a nominal scale?
Idenitiy (name)
Identity, order and distance is given, what measurement scale is used? (And practical purposes)
Interval scaling
What information is provided for a ordinal scale?
identity and order
What information is provided for a ratio scale?
identity, order, relative distance and origin (0)
What are types of measures?
self report, behavioural, physiological
What are ways to test for reliability?
Administer the same test twice and assess the correlation between the two test scores. A perfectly reliable test would give identical scores and 60% correlation is acceptable
What does positively skewed distribution indicate?
contains extreme high scores that have low frequency but does not contain low frequency, extreme low scores
What is the mode?
most occurring score
What is the median?
is the middle most score, the 50th percentile
What is a sample statistic?
Unbiased sample from total population
What are the measures of variability?
range, variance and standard deviation
What is the range? And advantages and disadvantages?
Difference between highest and lowest score. Easy to compute but affected by extreme scores and based on two scores
What is variance?
the mean squared deviation
What is the formula for variance?
s^2x = (sum(x-xbar)^2) / N
