WEEK 6 Flashcards
What are descriptive statistics?
Statistics that describe the data’
What types of statistics are descriptive statistics?
-Mean
Median
Mode
Standard deviation
What are inferential statistics?
Statistics tests that make inferences about data
What is distribution?
A distribution of data is basically a representation of data as a whole
What is the bell curve?
The shape of normal distribution
In a normal distribution, what happens to the averages?
Mean, mode, median are the same
What 2 things can happen to a curve of data?
- Become skewed
- Become kurtosis
What How does distribution become skewed?
When data is not symmetrical around the mean
If fhe data is skewed, what does the data have to be?
above 1 or -1
What is kurtosis?
Describes the pointyness of the distribution
What is platykurtic?
When distribution is flat or short
What is leptokurtic?
When distribution is tall and thin
What is a test statistic?
A statistic that summarises the data
How do we obtain test statistics?
Through inferential stats
What are common test stats?
F and T tests
What is null hypothesis statistical testing?
Statistical tests done to see whether which hypothesis we should reject and accept
What approaches are NHST based on?
- Fisher’s work- use of pfobability to test null hypothesis
- Reyman and Pearson- testing a null hypothesis against an alternative hypothesis
What are different ways to express probability?
Percentage
decimal
fraction
Usually done between 0 to 1
What is probability distribution?
The probability is represented through graphs to show the distribution of data
What is alpha level’?
The rule in psychology that probability is less than 5%
P< 0.005
When is data statistically significant?
When the probability is less than the alpha level
