very quick question about the 'intercept'

#1
If I am asked to state the intercept which one do I quote?

Estimate, Std error, t value or Pr(>|t|) ?

(If it makes any difference I am doing a regression using R)
 

TheEcologist

Global Moderator
#2
If I am asked to state the intercept which one do I quote?

Estimate, Std error, t value or Pr(>|t|) ?

(If it makes any difference I am doing a regression using R)

Code:
                Estimate   Std. Error t value Pr(>|t|)
(Intercept)     0.47637    0.69033    0.690    0.510
x              -0.08073    0.11126   -0.726    0.489

Residual standard error: 1.011 on 8 degrees of freedom
Multiple R-squared: 0.06176,    Adjusted R-squared: -0.05553 
F-statistic: 0.5266 on 1 and 8 DF,  p-value: 0.4887
Thats some r-output from a linear model.

Using summary(mymodel) as command. Are you really asking which line of output constitutes the intercept?

However if you are confused about the terms then here is some help:

Estimate
Std. Error
t value
Pr(>|t|)
 
#3
Code:
                Estimate   Std. Error t value   Pr(>|t|)
(Intercept)  0.47637    0.69033   0.690    0.510
x              -0.08073    0.11126  -0.726    0.489

Residual standard error: 1.011 on 8 degrees of freedom
Multiple R-squared: 0.06176,    Adjusted R-squared: -0.05553 
F-statistic: 0.5266 on 1 and 8 DF,  p-value: 0.4887
Thats some r-output from a linear model.

Using summary(mymodel) as command. Are you really asking which line of output constitutes the intercept?
Thanks for replying. Appreciate it.

Basically I have been asked to state the intercept of a certain regression. I know the intercept is where the line crosses the Y-axis. I always assumed the intercept value was the value after - (intercept) - like in your example. Yea I wish to know which line/value constitutes the intercept.

If I asked you to state the intercept of the above output what would you write?
 

TheEcologist

Global Moderator
#4
Thanks for replying. Appreciate it.
Basically I have been asked to state the intercept of a certain regression. I know the intercept is where the line crosses the Y-axis.
exactly

I always assumed the intercept value was the value after - (intercept) - like in your example. Yea I wish to know which line/value constitutes the intercept.
Be more specific in what you ask. The standard formula for linear regression is:

Y ~ ß0 + ß1 X

Where ß0 is the intercept and the value after that (ß1) is the slope.

If I asked you to state the intercept of the above output what would you write?
Again depends, for scientific purposes this would be best:

ß0=0.47637 (p = 0.510)
 
#5
Be more specific in what you ask.



Again depends, for scientific purposes this would be best:

ß0=0.47637 (p = 0.510)
Not really sure how to be more specific! Stats is my weak point!
This is for a regression in Psychology. I was looking at the impact of both between-subjects and within-subjects effects on depression. In this particular output I first dummy coded, then effect coded.

Your statement of the intercept looks very good to me. Thank you so much