Want to win a PS4? Go Premium and enter to win our High-Tech Treats giveaway. Enter to Win



Posted on 2011-09-07
Medium Priority
Last Modified: 2013-11-13
Hi Experts,

Please find attached an excel spreadsheet containing 2 charts and 4 data plots. What form of regression would most accurately model this data? At the moment I have a linear plot selected but it seems to me the data plots have a subtle s shape.
Question by:DColin
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
LVL 27

Accepted Solution

d-glitch earned 2000 total points
ID: 36499409
Those are actaully pretty good fits.

What is the data, and why do think there should be any fit at all?

I do see something in the data that looks vaguely sinusoidal.
You might try a Fourier Transform to see if that's the case.
LVL 84

Expert Comment

ID: 36499425
What relationship makes the most sense for the kind of data you have?

You can produce a fit to random noise and allowing more subtle shapes can produce better fits to random noise, but they would not be any more meaningful.

Asking for an arbitrary model for arbitrary data makes no sense.

You need to start by asking what kind of model makes sense for what the data represents.

Author Comment

ID: 36499491
Hi d-glitch:,

"You might try a Fourier Transform to see if that's the case."

Can excel do this?
Concerto Cloud for Software Providers & ISVs

Can Concerto Cloud Services help you focus on evolving your application offerings, while delivering the best cloud experience to your customers? From DevOps to revenue models and customer support, the answer is yes!

Learn how Concerto can help you.


Author Comment

ID: 36499516
Hi ozo,

The X-axis represents ability, 1 best 20 not best. Y-axis represents earnings.

I have no idea what relationships I am looking for. I was hoping these data plots would tell me what the relationships are.
LVL 18

Expert Comment

ID: 36501389
hi, I too thought the same as Dglitch, that there might be a sine wave in there, but there seems little logical explanation of why that would be, given your explanation of what the graphs represent.  

What your graphs show is that earnings and ability are positively correlated in a linear fashion.  Your X axis actually represents diminishing ability as you move along it, so the score 1 to 20 represents the amount of uselessness of the person

Author Comment

ID: 36501471
Hi deighton,

Would an explanation of the potential sine wave be that I have ranked the salespeople on the X-axis based on past performance. If I were to enumerate this rank it would not go 1,2,3 etc. but something like 100, 89,88,87,72,70,65 (best to worst). Do you think the non linearity of a ranking system is causing this?
LVL 18

Expert Comment

ID: 36501528
I doubt if there is a sine wave effect at all.  Seeing the sine wave was a risk of looking at things too closely.  It looks pretty much linear.  Absolute linearity is very unlikely to occur, there will always be some sort of variation.

Featured Post

Concerto's Cloud Advisory Services

Want to avoid the missteps to gaining all the benefits of the cloud? Learn more about the different assessment options from our Cloud Advisory team.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

What is Waterfall Model? Waterfall model is the classic Software Development Life Cycle method practiced in software development process. As the name "waterfall" describes, this development is flowing downwards steadily like waterfall, i.e., procee…
Introduction This article explores the design of a cache system that can improve the performance of a web site or web application.  The assumption is that the web site has many more “read” operations than “write” operations (this is commonly the ca…
This is a video describing the growing solar energy use in Utah. This is a topic that greatly interests me and so I decided to produce a video about it.
Finds all prime numbers in a range requested and places them in a public primes() array. I've demostrated a template size of 30 (2 * 3 * 5) but larger templates can be built such 210  (2 * 3 * 5 * 7) or 2310  (2 * 3 * 5 * 7 * 11). The larger templa…

636 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question