Statistics Flashcards
What are the sub-groups within categorical data?
Ordinal
Nominal
What are the subgroups within continuous data?
Discrete
Continuous (interval and ratio)
What does parametric data mean?
Normally distributed
What is the dependant variable?
The variable that is measured - the outcome variable
What does the R squared number relate to?
Tells you how much of the variation in one variable is due to its dependance on the other
When given an R number, what does this relate to?
Example:
R = 0.50 therefore 50%
So R squared = 0.5 x 0.5 = 0.25 (25%)
How do you tell if an effect is significant?
All values in the confidence interval will be on the same side of zero (i.e. all positive or all negative)
What does the confidence ratio represent?
The true population mean is likely to be
What is the null hypothesis?
The hypothesis that there will be no difference in treatments
What p value is accepted as statistically significant?
p equal to or less than 0.05
The smaller the p value =
The higher the statistical significance
If the p value is greater than 0.05 =
No statistical significance
Define sensitivity?
How useful a test is at ruling people in (i.e. the proportion of people who have a disease and test positive for it)
Define specificity?
How useful a test is at ruling people out (i.e. the proportion of people without a disease who test negative for it)
Interpretation of receiver operating characteristic curves?
The closer the line to the top left corner, the better i.e. the closer to 100% specificity and 100% sensitivity