Solving for Y using linear regression on HP17bii+

[Trulyrc]

Hello!

How do I solve this equation on the HP 17bii+?

You have a bldg with 15,000 SF; what is the price PSF of this bldg based on sales:

Sale 1. 12,000 SF; price PSF is $68.33
Sale 2. 14,000 SF; price PSF is $59.64
Sale 3. 16,000 SF; price PSF is $52.81
Sale 4. 18,000 SF; price PSF is $47.22

I know how to make the lists (one for SF and one for price PSF), but how do I add the bldg's 15,000 SF after that, to solve for its price PSF?

Your help is appreciated!

[Gene]

Try this:

HP-17BII+ Learning Module for Linear Regression

[Trulyrc]

Thank you. I had looked at this link previously.

However, the missing explanation is how to input the SF of the subject bldg, after having entered the two lists of sales.
How do you add that into the HP 17bii+ to then solve for Y?

[Gene]

Example 1 of the PDF shows how to do that.

In your problem, the SF would be X and the Price per SF is Y. Those are the same as the X and SALES in the example 1 of the PDF.

One you have entered your two lists as SF and PSF (perhaps, whatever you name them), then if you understand example 1 in the PDF you will know how to solve this problem.

Simple change X in the PDF to SF and SALES in the PDF to PSF and substitute those when working through the problem.

Note: You do not add the new SF to the previous SF list. You enter the SF for which you wish to predict a PSF just like the example showed for predicting Sales and X.

Work the PDF and make sure you understand how to predict Sales given a time period X and how to predict a time period X given a Sales value. Once you have that, you know how to work this.

Hope that helps.

[Trulyrc]

Definitely helped; I GOT IT! Thank you!

[Gene]

Great. Sorry it was unclear! :-)

That's the purpose of this forum. We all need help, myself included!

[Trulyrc]

No need to apologize! It was my hiccup in my mind... I thought those extra steps were for forecasting into the future only. But I guess in this case it's sort of a forecast as well. Makes sense now!
Thank you ever so much for helping me through that...thanks for this forum!!

[Gene]

Great. Return the favor by staying part of the community here and you'll find ways to help others. :-)

[Trulyrc]

Will do; I'm not going anywhere! Thanks again :-)