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happycow
 
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Default mutiple regression help


When doing a multiple regression in excel, what are the meaning of these
out puts (that's are all in the same table)

the fist column has my dependent variable which is labeled here
"Intercept" and the independent variables, X2, X3, X4, X5

the second columns labeled "Coefficients" i think this column has the
slope values of each independent variable; X2, X3, X4, and X5. These
slope variables are in relation to all the other variables, so the
slope of X2 is effected by by X3, X4 and X5. These slope values are the
measure of how each independent variable effects the dependent variable.
I'm guessing this allows me to predict where added data will go in the
correlation. So for example if I want to predict how a film will do (my
regression has to do with film gross) according to this data, i would
multiple my variables from that movie (budget (X2), first weekend gross
(X3), users ratings(X4) and MPPA rating (X5)) to the corresponding
Coefficients values in this column. If what i am saying is right (or at
least partially right), i don't know what the value of Intercept is for,
since is from the dependent variable, it shouldn't have a slope value.


The second column which is labeled "Standard Error" I'm guessing (if
what I am saying above the coefficients values are right) is the
accuracy of the predications that can be made. I'm guessing the larger
the number the bigger the error.

The fourth column which is labeled "t Stat" i have no clue what it
means and how it contributes to my regression. I'm thinking it's some
type of testing but i don't understand what it's testing and why.

The fifth column which is labeled "P-value" is again something I don't
understand. I think it has to do something with "t-Stat". My other
theory is that it has to do something with probability. I really don't
know though.

The next two columns labeled "Lower 95%" and "Upper 95%", i believe
this is the limits of my correlations. I think that this allows one to
say that "i am 95% sure that the predicted data that lies between these
lowers and uppers can be predicted by the accuracy of my the values in
my "coefficients" column.

I also am wondering about the graph outputs, the first graph "Line Fit
Plot" outputs 4 scatter diagrams for each of my 4 independent
variables. the graphs looks like their comparing my dependent variable
(on the y axis) to a independent variable on the x axis. Is this just
showing the correlation and relationship of each independent variable
to the dependent variable. For each individual diagram, Is the
comparison being made and liner relationship (the direction the lines
seem to be going; positive, negative or none) based on just the
independents variable and the dependent variable, or is the independent
variable's slope taking into account the other 3 independent variables?

The second graph; the "Residual Plot Graph", does this show the measure
of stand error for each point? and the closer to 0 a point gets the
lesser the error?


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happycow
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