Thread: p value of the constant, can I ignore it?

1. p value of the constant, can I ignore it?

I'm analysing the influence of various factors on hare harvests in a specific are.
E.g. How do the hare harvests change when the fox harvests increase.

Term Coef | SE-Coef | T-Value | P-Value
Constant | 415.0 | 28.7 | 14.46 | 0.000
Annual fox harvest | -1.054 | 0.193 | -5.45 | 0.001

Here the p value of the constant is highly significant.

But for other comparisons, such as the number of worker employed in agricultre (indicator for the level of mechanisation= the P value of the constant is very high:

Term | Coef | SE Coef | T-Value | P-Value
Constant | -12.4 | 71.0 | -0.17 | 0.868
Number of workers | 0.1220 | 0.0249 | 4.89 | 0.005

What does that mean? I somewhere red that my prediction around the origin is going to be inaccurate. Does this matter, and what does it mean for the relationship between the number of workers and the hare harvest?

I couldn't format the tables, sorry. hope you still get it.

2. Re: p value of the constant, can I ignore it?

hi,
the interpretation of the constant is often irrelevant - in your case it would be the average hare harvest in the case of 0 employed workers - possibly a completely mechanised agriculture with no workers? So, in general one does not ignore the constant because of the p value but because the X=0 case is outside the range of realistic values. One trick would be to repeat the analéysis with mean (or median) centered X-es in which case the constant is easily interpretable - the Y at the mean (or mediean) X.

regards

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