Probability Flashcards
1
Q
What is probability ?
A
- A measure of likelihood that a particular event will occur
- where 0 indicates statistical impossibility and 1 shows statistical certainty
- Probability of the result being due to chance is when probability is greater than 0.05
- Psychologists can never be 100% certain, so heir is an accepted level of significance (0.05)
- By having 0.05 it balances type 1 and type 2 errors
2
Q
When is 0.01 used as the probability ?
A
- When their is a risk to life
- Drug therapy
3
Q
What are type 1 errors ?
A
- false positives
- wrongly accepting the null hypothesis
- if significant probability was too lenient
- e.g. 0.1 rather than 0.05
4
Q
What are type 2 errors ?
A
- false negatives
- wrongly accepting the null hypothesis
- if significance of possibility is too strict/stringent
