Theme 6 - Statistical Measurements Flashcards
(18 cards)
What is a Bivariate Data?
Set of Data with two variables
What is the goal of Statistical Analysis?
Find the relationship between two variables
Define Correlation.
Statistical relationship between two variables
What indicates a Positive Correlation?
When one variable increases, the other increases
What indicates a Negative Correlation?
When one variable increases, the other decreases
What does a Correlation Coefficient quantify?
The strength of the linear relationship between a pair of variables and direction of correlation
What is Regression?
Relationship in the form of an equation useful to make predictions in data
What is an example of a bivariate analysis in cancer epidemiology?
Incidence of cancer vs number of cigarettes smoked by individuals
What is the correlation observed between the number of cigarettes smoked and incidence of cancer?
Positive Correlation
What correlation coefficient range indicates a very strong correlation?
0.90–1.00 (or –0.90 to –1.00)
What correlation coefficient range indicates a strong correlation?
0.70–0.90 (or –0.70 to –0.90)
What correlation coefficient range indicates a moderate correlation?
0.50–0.70 (or –0.50 to –0.70)
What correlation coefficient range indicates a weak correlation?
0.30–0.50 (or –0.30 to –0.50)
What correlation coefficient range indicates negligible correlation?
0.00–0.30 (or –0.00 to –0.30)
True or False: Correlation implies a causal relationship.
False
What are some possible explanations for observed correlations?
- By chance
- Variable X causes Variable Y
- Variable Y causes Variable X
- Another variable causes X and Y
What is required to determine causation?
Many experiments of large datasets
What can be performed to further examine a correlation?
Testable predictions
