Splines.p96.tips - Further suggestions for doing Spline...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Further suggestions for doing Spline problems 1-3 on page 96 1) If there are several levels, try to write the most complicated quantitative model for the level that is most complicated. For example if we had y=profit and x 1 job size and we had 3 engineers J,S and A and the relationships between y and x 1 were first order, second order and third order for J,S,A respectively, we would want to first focus on writing a third order relationship between y and x 1 as reflected in the data for A. 2. In our problem x 2 takes on the values A and B. We can NOT use x 2 in an equation for E(y) directly, rather we need to define a new variable(s) that has NOT been used before, dummy (0/1) variable(s) for the qualitative variable x 2 (like perhaps, if x 3 has not been used, x 3 = 1 if B, 0 otherwise). 3. When we have a KNOT, we want to define a 0/1 variable to handle terms above and below the knot and include this in the equation so that you write one equation for E(y), not a separate equation for E(y) for values below the KNOT and...
View Full Document

This document was uploaded on 11/01/2011 for the course MANAGEMENT 385 at Rutgers.

Ask a homework question - tutors are online