Research Methods (Year 2) Flashcards
What are statistical tests?
Used to determine whether a significant difference or correlation exists
When is a null hypothesis rejected?
When a p-value (probability) is less than or equal to significance levels
What are the 8 statistical tests?
- Chi-squared
- Sign test
- Mann-Whitney
- Wilcoxon
- Spearmans rho
- Unrelated t-test
- Related t-test
- Pearsons r
What are the 6 tests of difference?
- Chi-squared
- Mann-Whitney
- Unrelated t-test
- Sign test
- Wilcoxon
- Related t-test
What are the 3 tests of association and correlation?
- Chi-squared
- Pearsons r
- Spearmans rho
Which test is both a test of difference and test of correlation/association?
Chi-squared
What does it mean when an investigation is statistically significant?
It’s unlikely to be explained solely by chance or random factors.
What does it mean when a design is unrelated and give an example
Participants in each condition of the design are different e.g independent groups
What does it mean when a design is related and given an example
The same or similar ‘matched’ participants are used in all conditions of the design e.g repeated measures, matched pairs
What is nominal data?
Data is represented in the form of categories
What is ordinal data?
Data is sorted into an order or scale
What is interval data?
Data based on numerical scales that include units of equal, precise data
What are the three levels of measurements?
- Nominal data
- Ordinal data
- Interval data
What is the feature of nominal data?
The data is discrete so one item can only appear in one of the categories
What is a drawback of ordinal data?
It lacks precision because it is based on subjective data rather than objective measures
What is the best level of measurement and why?
- Interval
- The most precise and sophisticated form of data
What is probability?
A measure of the likelihood that a particular event will occur (0 indicates statistical impossibility and 1 statistical certainty)
What is a critical value?
When testing a hypothesis, the numerical boundary/cut-off between acceptance and rejection of null hypothesis
What the usual level of significance in psychology?
0.05 (5%)
What is a type I error?
When the null hypothesis is rejected and the alternative hypothesis is accepted
What is a type II error?
When the null hypothesis is accepted and the alternative hypothesis is rejected (false negative)
- Conculde theres no effect/difference when there is
What is the difference between a one-tailed and two-tailed test?
A one-tailed test is if the hypothesis was directional and a two-tailed
What is falsifiability?
The principle that a theory cannot be considered scientific unless it admits the possibility of being proven untrue
What is a paradigm?
A set of shared assumptions and agreed methods within a scientific discipline
