Bivariate Statistics Flashcards
Why do you have to take note of the saved function f when doing a linear regression?
So you can use the saved function later to predict outputs.
You click the var button in a calculator tab and choose the correct function.
What would a scatter plot look like if r = 1 ?
What would a scatter plot look like if r = 0.9 ?
What does this symbol represent?
Pronounced “x bar”, this symbol represents the mean for the variable x.
What is the fancy calculator name for “line of best fit “ ?
Linear Regression (mx+b)
What does it mean if r = 0 ?
There is no correlation between the two variables.
What are the lowest and greatest values r can be?
The lowest r can be is -1.
The greatest r can be is +1.
What would a scatter plot look like if r = 0 ?
What does b stand for in the equation for a straight line?
y = mx + b
b is the y-intercept
What does it mean if r = 1 ?
The two variables are perfectly positively correlated.
What would a scatter plot look like if r = -0.5 ?
What is the equation for the regression line (aka any straight line)?
What would a scatter plot look like if r = 0.5 ?
What are the many names we use for correlation?
All of these names refer to the same thing.
- Pearson correlation coefficient
- Pearson product-moment correlation coefficient
- Pearson’s r
- bivariate correlation
What would a scatter plot look like if r = -1 ?
For which x-values are you allowed to use your linear regression predictions?
Only for those that are inside the domain of the original data.
This means, if the scatter plot only has data from x between 2 and 10, you can only use predictions for x-values between 2 and 10.
What does this symbol represent?
Pronounced “y bar”, this symbol represents the mean for the variable y.
What letter do we use for correlation?
r
What does m stand for in the linear regression line?
y = mx + b
m is the gradient
What would a scatter plot look like if r = -0.9 ?
What does it mean if r = -1 ?
The two variables are perfectly negatively correlated.
Where do I find b, the y-intercept of the linear regression line in the calculator output?
Where do I find m, the gradient of the linear regression line, in the calculator output?
