Please comment on the following questions:
1) What is the difference between correlation and association?
2) If a scatterplot shows a very strong linear relationship, what value(s) should the correlation be close to?
3) If a scatterplot shows a very weak linear relationship, what value(s) should the correlation be close to?
4) Is it possible to have a strong association, but a weak correlation?
5) What is a lurking variable? What kind of affect can it have on the relationship between two quantitative variables?
1. An association is any relationship between two measured quantities. A correlation is a LINEAR relationship only.
ReplyDelete2. The value should either be close to 1 or close to negative 1.
3. The value should be close to zero.
4. Yes.
5. A lurking variable correlates with both the predictor and the response variables.
1. Correlation is a statistical measurement of the relationship between two variables. Association is any relationship between two measured quantities that renders them statistically dependent.
ReplyDelete2. Should be close to 1 or to negative 1.
3. values should be close to zero.
4. yes when the form is nonlinear
5. Lurking value is the observed relationship between the independent variable and the dependent variable.
1) Association measures any relationship between variables and correlation measures the strength of the linear association between quantitative variables.
ReplyDelete2) Closer the coefficients are to +1.0 and –1.0, greater is the strength of the relationship between the variables.
3) Close to 0
4) Yes
5)It's a extraneous variable that correlates (positively or negatively) with both the dependent variable and the independent variable.
1. An association is a relationship between two variables and a correlation is looking to see if there is a linear line and see what kind of strength it has.
ReplyDelete2. The correlation should be close to 1.
3. If it is weak the correlation should be close to 0.
4. Yes
5. A lurking variable is one that has a big affect on the data.