independent variable
always manipulated, controlled by experimenter
- it is independent because it is not controlled by the participants behaviour is not influenced by the dependent variable
- has two levels: drug vs placebo, drug 1 vs drug 2
quasi-independent variable
like an IV but it cannot be randomly allocated
- used for measuring natural variables (biological sex, age)
- these natural variables cannot be manipulated so they are grouped into categories
- used for measuring attribute/person variables
- individual difference variable that fall on a spectrum (anxiety, level of risk taking)
dependent variable
assess or measure the effects of the independent variable
- measures a behaviour or response to the independent variable
- measured not manipulated
operationalism
detailed description of the procedures or operations used to measure or manipulate the variables
- specify exactly what you mean in the hypothesis, to be measured correctly,
Steps of the Scientific Method
- Observation
- Hypothesis
- Test
- Analyse and Conclude
- Update or Discard
- Theory
- Observation
→ all begin with an initial observation
- Most are based on past research
- Point of interest for further research, gaps in the literature
- Must be able to find a way to collect observable evidence
- Replication to find the same results
- Hypothesis
→ very specific statement about the predicted/expected relationship between variables
- Should talk about the expected relationship between the independent and dependent variables
- Predicts effect of manipulated variable on measured variable
- States that relationship should exist between variables, expected direction of the relationship between the variables and how this might be measured
- Test
Design experiment
- Good experimental design
- Collect appropriate data (is it able/the best design to answer the question)
- Control as many aspects as possible
Research Methods
- Is the experiment reliable or valid
- Analyse and Conclude
Consider whether data supports evidence
- Sufficient?
- Results statistically significant?
- Are further studies required
Conclude
- Interpretation of evidence
- Based on results
- Explain the results
- Update or Discard
Scientific method is dynamic
- Must be able to update when there is a lack of data to support it
- Must be able to discard when evidence refutes it
Requires aspects of critical thinking
- Open to the possibility that you are incorrect
- Evaluation of the evidence
- Ability to change your opinion with new evidence
- Theory
→ organised system of assumptions and principles that attempts to explain certain phenomena and how they are related
- Many hypotheses are tested and data
collected before theories are formed - Lead to further questions
The nature of changes to the scientific method
it will not tell you what is true or proven, it might change
- Dynamic process
- Peer reviewed
- Never claim to find one cause
- Should always be clear
The Goals of Science
- description (observing phenomena in a systematic manner)
- prediction (make predictions from one variable to another)
- explanation
description (goal of science)
observing phenomena in a systematic manner
- It is important to understand what is happening before making a prediction on something
Drugs example
- To find if there is a relationship between the type of pill and the rates of overdose, you need to describe the types of pills consumed, the contents, the number of overdoses
prediction (goal of science)
make predictions from one variable to another
- Use the measurement of one variable to predict the measurement of another variable
- Correlation between two variables
Drug example
- Is there a relationship between offering drug testing and the level of overdose
explanation (goal of science)
- End goal
- Testing a causal relationship, requiring research methods, experimental design and requires statistics to evaluate the data
- Always more or less more than one way to explain something, so the explanation must have this in mind
Pseudoscience
→ a collection of statements, beliefs or practices that claim to be factual and scientific
How do you tell the difference between Pseudoscience and Science?
pseudoscientists use scientific methodology and techniques, but they may not be applied correctly nor are they open to changing the theory based on different evidence and so they are limited in their use of this method
- it doesn’t change when sufficient evidence suggests that the theory is wrong
- the claim should be updated if there is no evidence
What are some similarities between Pseudoscience and Science?
- subject matter overlaps (astrology is connected to physics for example)
- the goals often overlap (to make descriptions and predictions)
Pseudoscience is Not Science
It is scientific thinking that has been flawed but refuses to change
- involves biased evidence
Pseudoscience Example - Astrology Experiment (Carlson, Shaw 1985)
- double-blind study to remove bias
- volunteers provided information to have their chart done
- 28 astrologers were given one chart and three personalities
- 1/3 chance if they are just guessing
Results
- performed at chance level
- clear research question, hypothesis and interpretation of outcomes
PT Barnum Effect
psychological phenomenon whereby individuals give high accuracy ratings to descriptions of their personality that are supposedly are tailored specifically to them, when they are in fact vague and general enough to apply to a wide range of people
- applicable to astrology
Homeopathy Example (Pseudoscience)
idea that diluted version of what has caused the problem can also cure it
problems
- illogical, not a scientific claim
- not testable, no empirical evidence
- testimonial evidence (biased sampling, has only used testimony’s of the people its worked for)
- extraordinary claim requires extraordinary research
