Feature Engineering Studio

October 14, 2013

Iterative Feature Refinement

Who here

• Used the Excel Equation Solver• Did not use the Excel Equation Solver

Excel Equation Solver Users

• Sort yourself by the town you were born in (in Roman letters)

Excel Equation Solver Users

• Pick one feature

• What feature did you improve?• What parameter did you adjust?• What was the original and final value?• How big an improvement did you obtain?• Did this process change the meaning of the

feature?

Everyone Else

• Sort yourself by the town you were born in (in Roman letters)

Everyone Else

• Pick one feature

• What feature did you improve?• What parameter did you adjust?• What values did you try?• How big an improvement did you obtain?• Did this process change the meaning of the

feature?

Comments? Questions? Thoughts?

Question

• Is the excel equation solver likely to change the meaning of the feature more than hand processes?

Question

• Is it a good thing or a bad thing, when your feature changes meaning due to refinement?

Feature Parameter Space

• I need a volunteer who had a final best feature that was quite different from their original feature

One interesting exercise

• I need a volunteer who had a final best feature that was quite different from their original feature

• Please bring up your laptop or a flash drive with your data set

Making…

• A line graph

• X axis – parameter value• Y axis – model goodness

Another volunteer?

• Would anyone else like to look at their feature this way?

• Multiple volunteers are welcome

What does it mean?

Questions? Comments? Thoughts?

Assignment 6

• Feature Adaptation“This One’s For Nikolai Ivonavich Lobachevsky”

Nikolai Ivonovich Lobachevsky(by Tom Lehrer)

“I will never forget the day I first met the great Lobachevsky.In one word he told me the secret of success in mathematics:”

Nikolai Ivonovich Lobachevsky(by Tom Lehrer)

“I will never forget the day I first met the great Lobachevsky.In one word he told me the secret of success in mathematics:Plagiarize!”

Nikolai Ivonovich Lobachevsky(by Tom Lehrer)

“I will never forget the day I first met the great Lobachevsky.In one word he told me the secret of success in mathematics:Plagiarize!”

“Only be sure to always call it – please – research.”

To be clear…

• Plagiarism: bad

To be clear…

• Plagiarism: bad

• Borrowing ideas (and citing them): good

To be clear…

• Plagiarism: bad

• Borrowing ideas (and citing them): good

• We all clear?

Assignment 6

• You need to find a previous paper that uses one or more features that can be potentially translated to your current analysis

• Find the paper• Try at least one feature in your own data set

Assignment 6

• You need to create a 5-minute presentation– Time yourself to make sure it only runs 5 minutes– To be presented in class next Monday

Assignment 6

• This presentation should discuss– The paper you drew inspiration from– Give a full citation and show us pictures of as many

authors as you can find– The construct being predicted in this paper– The context/data set in this paper– The feature you decided to adapt– The feature you ended up creating– Differences between the original paper’s feature and

your feature– The goodness of your feature in your data set

What if you can’t find a paper?

What if you can’t find a paper?

• You can find a paper

What if you can’t find a paper?

• You can find a paper• Try google scholar

What if you can’t find a paper?

• You can find a paper• Try google scholar• Email me – but only after you have spent at

least 2 hours searching the web

Questions? Comments?

Upcoming Classes

• 10/16 No special session today

• 10/21 Feature Adaptation– Assignment 6 due

• 10/23 Special Session on Building Prediction Models

Upcoming Classes

• 10/28 Feature Reuse

• 10/30 No special session today

Thank you!