Hot answers tagged

19 votes
Accepted

If X=Y+Z, Is it ever useful to regress X on Y?

If you know $X = Y + Z$ and you have $Y$ and $Z$ measured, why would you need to run a regression of $X$ on $Y$ and $Z$? It provides no additional information and does not allow you to make "...
user avatar
  • 22.5k
6 votes

If X=Y+Z, Is it ever useful to regress X on Y?

Linear regression is a tool that is used to achieve a goal. So any answer will depend on the goal to be achieved. As said already in the answer of @Noah, if you already know $X$, $Y$, and $Z$, I can't ...
user avatar
5 votes

If X=Y+Z, Is it ever useful to regress X on Y?

Two people step on a scale. The scale outputs only the total weight of the couple. If you know the weight of the first person ($Y$) can you guess what the scale will output ($X$) without knowing ...
user avatar
  • 1,288
2 votes
Accepted

How does a small range of the dependent variable affects linear regression?

Since your DV is naturally bounded between 0 and 100, but you have only observed values larger than 96, the lower bound is probably not going to be a problem. (Otherwise I would have looked at a beta ...
user avatar
1 vote
Accepted

Linear regression decimal residuals below and above don't match exactly

Rounding is the culprit. Do it all with fractions to get the exact zero. $$ x_1=12.2=\dfrac{366}{30}\\ x_2=15.5=\dfrac{465}{30}\\ x_3=16.6=\dfrac{498}{30}\\ \bar x = \dfrac{443}{30}\\ x_1-\bar x = \...
user avatar
  • 32.6k
1 vote

Linear regression with Poisson distributed error term?

The model itself is quite weird and here are some example: The response variable is count but the regression model is Linear. So you would expect to see some "Impossible" prediction like 7....
user avatar
  • 404

Only top scored, non community-wiki answers of a minimum length are eligible