Psychology and Science notes
Ch 1 -Introduction
Significance the result you obtained is unlikely to occur if the factor you study does not hold
- Significance level of 5% normally used- the probability that the results were caused by
chance is less than 5%
Submit article to scientific journal peer review (check if results are viable) if accepted it will
be published
Reproducibility outcome should be independent, but the same effects should be found
- Journals usually don’t accept studies which are just replications of previous work
- Reputation of journals based on how many times the articles in the journal have been cited so
publishing replicated studies does not benefit the reputation of the journal
- When replicated significance goes down- example: 0.95x 0.95= 0.90 (1-0.90=0.1-10%
significance level)- this is just 1 study that has been replicated once
1-0.95N
What makes a scientist ‘successful’ number/impact of publications, H index, grants and
rewards
- They get an incentive to cheat to look better/make more
- Scientific misconduct = fraud
Pseudo explanations can explain everything but they don’t rule out anything and they don’t
allow you to make hypotheses
Chapter 2- Logical Positivism
Logical positivism (empiricism) the standard view of science- distinguishing between real
scientific knowledge and false knowledge- emphasis on the importance of verification of science
- Science is based on facts that you get from observing/experimenting based on facts you
derive generalizations that you can further test gradually you develop knowledge about the
topic and this knowledge is secure and based on scientific proof
- Vienna circle (Wiener Kreis) attributed for the views of logical positivism
- The nature of psychology was influenced by logical positivism- not the other way around
- Aims to provide a demarcation criterion between real knowledge and nonsense
Logical positivism came after positivism and can be based on Logic and observable facts
which allow us to create a basis for the scientific world and its method
- Also known as logical empiricism or inductivism
- According to LP, science is made obtaining observations to obtain facts, derive
generalizations from the facts (laws) and derive predictions (hypotheses) from the
generalizations to test them
Hypothesis potential explanation-specific enough to make a prediction
- When a hypothesis makes a selection between relevant and irrelevant facts, it can be tested
and then rejected or accepted on the basis of the outcome
, Positivism science should only be concerned with observations that could be made and
repeated by anyone- objective- completely based on observations
Law of nature when a generalization is sufficiently tested and supported by observation- the
highest form of empirical knowledge that humans can obtain
Theoretical concepts always traceable to observation and based on observable facts
- Uses operationalization you define a theoretical concept in terms of the way you can
observe/measure it
LP uses 2 forms of inference induction and deduction
- Induction used to derive generalizations
Induction generating a general statement from individual observations
- Used to link facts and laws in LP
- Uses terms ‘all’ or ‘no’
- Example- all people with MDD have a sleep disorder
- General statements can be laws of nature- general law of nature
Deduction generating an individual statement (conclusion) derived from other statements
(premises)- deduction is rock solid
- Using established generalizations as the basis of deductions
- Deduction the valid derivation of a statement on the basis of other statements
- Also known as syllogism- used for explanations and predictions
- Provides an explanation when the conclusion has been drawn without an explanation
- Categorical claims phrases using ‘all’ or ‘some’
- Initial condition the second premise of a syllogism- states a specific observation
Any explanation must be based on a deduction in which one or more general laws provide
explanatory power deductive nomological (D-N) model of explanation or prediction
- Whole set of premises used in deduction = Explanans
- The conclusion of deduction = Explanandum
LP also uses deduction to test a hypothesis
Falsification testing a hypothesis and finding it is not true
Verification when you test a hypothesis and it is true
Chapter 3- Popper and Falsificationism
Karl Popper criticized verification, was a member of the Vienna Circle however was a critic of
LP
- Verification does not prove a hypothesis- instead replaced verification with the term
confirmation- confirmation of a hypothesis not proof- Popper rejected this too
- Popper believes that the only certainties in science that we can get are from its failures
Falsification- the only certainties in science are the failures of science- the falsifications that
science has obtained- the best way knowledge can grow is through our attempt to correct our
errors- provides certainty
- Induction cannot produce certainty as the number if observations used in an induction will
always be limited compared to the generalizations made
- A theory cannot be falsified if it does not have empirical content
Dogmatic thinking (dogmatism)- popper’s description on the idea that science must be based only
off observations Very closed minded way of thinking
Ch 1 -Introduction
Significance the result you obtained is unlikely to occur if the factor you study does not hold
- Significance level of 5% normally used- the probability that the results were caused by
chance is less than 5%
Submit article to scientific journal peer review (check if results are viable) if accepted it will
be published
Reproducibility outcome should be independent, but the same effects should be found
- Journals usually don’t accept studies which are just replications of previous work
- Reputation of journals based on how many times the articles in the journal have been cited so
publishing replicated studies does not benefit the reputation of the journal
- When replicated significance goes down- example: 0.95x 0.95= 0.90 (1-0.90=0.1-10%
significance level)- this is just 1 study that has been replicated once
1-0.95N
What makes a scientist ‘successful’ number/impact of publications, H index, grants and
rewards
- They get an incentive to cheat to look better/make more
- Scientific misconduct = fraud
Pseudo explanations can explain everything but they don’t rule out anything and they don’t
allow you to make hypotheses
Chapter 2- Logical Positivism
Logical positivism (empiricism) the standard view of science- distinguishing between real
scientific knowledge and false knowledge- emphasis on the importance of verification of science
- Science is based on facts that you get from observing/experimenting based on facts you
derive generalizations that you can further test gradually you develop knowledge about the
topic and this knowledge is secure and based on scientific proof
- Vienna circle (Wiener Kreis) attributed for the views of logical positivism
- The nature of psychology was influenced by logical positivism- not the other way around
- Aims to provide a demarcation criterion between real knowledge and nonsense
Logical positivism came after positivism and can be based on Logic and observable facts
which allow us to create a basis for the scientific world and its method
- Also known as logical empiricism or inductivism
- According to LP, science is made obtaining observations to obtain facts, derive
generalizations from the facts (laws) and derive predictions (hypotheses) from the
generalizations to test them
Hypothesis potential explanation-specific enough to make a prediction
- When a hypothesis makes a selection between relevant and irrelevant facts, it can be tested
and then rejected or accepted on the basis of the outcome
, Positivism science should only be concerned with observations that could be made and
repeated by anyone- objective- completely based on observations
Law of nature when a generalization is sufficiently tested and supported by observation- the
highest form of empirical knowledge that humans can obtain
Theoretical concepts always traceable to observation and based on observable facts
- Uses operationalization you define a theoretical concept in terms of the way you can
observe/measure it
LP uses 2 forms of inference induction and deduction
- Induction used to derive generalizations
Induction generating a general statement from individual observations
- Used to link facts and laws in LP
- Uses terms ‘all’ or ‘no’
- Example- all people with MDD have a sleep disorder
- General statements can be laws of nature- general law of nature
Deduction generating an individual statement (conclusion) derived from other statements
(premises)- deduction is rock solid
- Using established generalizations as the basis of deductions
- Deduction the valid derivation of a statement on the basis of other statements
- Also known as syllogism- used for explanations and predictions
- Provides an explanation when the conclusion has been drawn without an explanation
- Categorical claims phrases using ‘all’ or ‘some’
- Initial condition the second premise of a syllogism- states a specific observation
Any explanation must be based on a deduction in which one or more general laws provide
explanatory power deductive nomological (D-N) model of explanation or prediction
- Whole set of premises used in deduction = Explanans
- The conclusion of deduction = Explanandum
LP also uses deduction to test a hypothesis
Falsification testing a hypothesis and finding it is not true
Verification when you test a hypothesis and it is true
Chapter 3- Popper and Falsificationism
Karl Popper criticized verification, was a member of the Vienna Circle however was a critic of
LP
- Verification does not prove a hypothesis- instead replaced verification with the term
confirmation- confirmation of a hypothesis not proof- Popper rejected this too
- Popper believes that the only certainties in science that we can get are from its failures
Falsification- the only certainties in science are the failures of science- the falsifications that
science has obtained- the best way knowledge can grow is through our attempt to correct our
errors- provides certainty
- Induction cannot produce certainty as the number if observations used in an induction will
always be limited compared to the generalizations made
- A theory cannot be falsified if it does not have empirical content
Dogmatic thinking (dogmatism)- popper’s description on the idea that science must be based only
off observations Very closed minded way of thinking
