Linear regression
Hello
What does it mean that the residuals in linear regression is
normal distributed? Why is it only the residuals that is, and not
the "raw" data? And why do we want our residuals to be normal?
What is a simple linear regression model? What does
the value of the linear correlation coefficient tell us?
Please type the answer as I have diffculties
understanding handwritten answers. Thanks.
8. Linear equations and the regression line
Suppose a graduate student does a survey of undergraduate study
habits on his university campus. He collects data on students who
are in different years in college by asking them how many hours of
course work they do for each class in a typical week. A sample of
four students provides the following data on year in college and
hours of course work per class:
Student
Year in College
Course Work Hours per...
Find a study that uses linear regression and a line of best fit.
What is the Correlation Coefficient? What conclusions can you make
about the data? Is there a correlation and how strong is it?
Find the linear regression line for the following table of
values. You will need to use a calculator, spreadsheet, or
statistical software.
Enter your answer in the form y=mx+b, with m and b both rounded
to two decimal places.
x
y
3
6.03
4
9.65
5
11.49
6
11.57
7
12.96
8
14.97
9
16.31
10
17.43
11
18.55
How are the slope and intercept of a simple linear regression
line calculated? What do they tell us about the relationship
between the two variables? Give example of problem.
How are the slope and intercept of a simple linear regression
line calculated? What do they tell us about the relationship
between the two variables? Also, give an example.
What is a linear regression analysis? What does it
provide you? Your answer should address development of a linear
response equation and associated uncertainty in
prediction.
Draw a scatterplot with a linear regression line for which the
condition E(ui|Xi)=0 does not hold for all Xi, but E(ui)=0. Be sure
to explain how your scatterplot satisfies these criteria.