# Linear regression problem

1. Oct 21, 2009

### mlarson9000

1. The problem statement, all variables and given/known data
Evaluate the partial effect of age of a firm on growth.(evaluated at the means)

2. Relevant equations

Growth=$$\beta$$0+$$\beta$$1age+$$\beta$$2age^2+$$\beta3$$size*age+$$\beta$$4plant*age

3. The attempt at a solution

We're supposed to do something like this:
Growth=$$\beta$$0+$$\beta$$1age+$$\beta$$2(age-$$\mu$$a)^2+$$\beta$$3(size-$$\mu$$s)*(age-$$\mu$$a)+$$\beta$$4(plant-$$\mu$$p*(age-$$\mu$$a)

or

Growth=$$\beta$$0+$$\beta$$1age+$$\beta$$2age^2+$$\beta$$3(size-$$\mu$$s)*(age-$$\mu$$a)+$$\beta$$4(plant-$$\mu$$p*(age-$$\mu$$a)

=$$\beta$$1+2$$\beta$$2age

=$$\beta$$1+2$$\beta$$2$$\mu$$

Last edited: Oct 21, 2009