LFD Book Forum How to solve example 5.3 step per step?
 User Name Remember Me? Password
 Register FAQ Calendar Mark Forums Read

 Thread Tools Display Modes
#1
02-28-2015, 07:17 AM
 qwertyqwertz Junior Member Join Date: Feb 2015 Posts: 4
How to solve example 5.3 step per step?

Hi folks,

I wonder how to solve the example 5.3 on page 174? I tried to come up with the right solution, but the outcome doesn't make sense.

These are the given numbers:
Hitrate: 52.1%
Number of test days: 500

The correct result is a cumulative profit of 22%.

How do I get 22%?

Thanks a lot and have a nice day!
#2
02-28-2015, 08:01 PM
 yaser Caltech Join Date: Aug 2009 Location: Pasadena, California, USA Posts: 1,478
Re: How to solve example 5.3 step per step?

Quote:
 Originally Posted by qwertyqwertz Hi folks, I wonder how to solve the example 5.3 on page 174? I tried to come up with the right solution, but the outcome doesn't make sense. These are the given numbers: Hitrate: 52.1% Number of test days: 500 The correct result is a cumulative profit of 22%. How do I get 22%? Thanks a lot and have a nice day!
The hit rate is the percentage of days you got the direction right, while the profit takes into consideration how much money you made (or lost) when you got the direction right (or wrong). You can read the 22% directly off the figure on page 175 as the final value at day 500.
__________________
Where everyone thinks alike, no one thinks very much
#3
03-01-2015, 08:34 AM
 qwertyqwertz Junior Member Join Date: Feb 2015 Posts: 4
Re: How to solve example 5.3 step per step?

Quote:
 Originally Posted by yaser The hit rate is the percentage of days you got the direction right, while the profit takes into consideration how much money you made (or lost) when you got the direction right (or wrong). You can read the 22% directly off the figure on page 175 as the final value at day 500.
Hello Yaser,

Thank you very much for taking the time to answer my question! Somehow I didn't made the connection between that specific paragraph on page 174 and the figure on page 175 which is quite silly, because it follows right after.

In addition, let me thank you and your co-authors for your brilliant and concise book "Learning from Data". It was a delight to read! Though, the mathematical notation was sometimes a little odd for my taste. But this is just a minor critic that doesn't hurt the overall reading experience.

The book shipped without any problem from the Amazon US store to Germany. The delivery took about six weeks.

The only thing I found lacking from the book was a chapter about evaluation measures. I think this is a critical point that would help the reader understand why a certain model is better in some regards than another. Moreover, it would be really nice if you could provide some examples to illustrate the different measures since this is often quite dependent on the context in which the model in question is applied.

Again, let me thank for your excellent book and online course!
#4
03-01-2015, 08:28 PM
 yaser Caltech Join Date: Aug 2009 Location: Pasadena, California, USA Posts: 1,478
Re: How to solve example 5.3 step per step?

Thank you for the information and the feedback.
__________________
Where everyone thinks alike, no one thinks very much

 Thread Tools Display Modes Linear Mode

 Posting Rules You may not post new threads You may not post replies You may not post attachments You may not edit your posts BB code is On Smilies are On [IMG] code is On HTML code is Off Forum Rules
 Forum Jump User Control Panel Private Messages Subscriptions Who's Online Search Forums Forums Home General     General Discussion of Machine Learning     Free Additional Material         Dynamic e-Chapters         Dynamic e-Appendices Course Discussions     Online LFD course         General comments on the course         Homework 1         Homework 2         Homework 3         Homework 4         Homework 5         Homework 6         Homework 7         Homework 8         The Final         Create New Homework Problems Book Feedback - Learning From Data     General comments on the book     Chapter 1 - The Learning Problem     Chapter 2 - Training versus Testing     Chapter 3 - The Linear Model     Chapter 4 - Overfitting     Chapter 5 - Three Learning Principles     e-Chapter 6 - Similarity Based Methods     e-Chapter 7 - Neural Networks     e-Chapter 8 - Support Vector Machines     e-Chapter 9 - Learning Aides     Appendix and Notation     e-Appendices

All times are GMT -7. The time now is 03:51 AM.

 Contact Us - LFD Book - Top

Powered by vBulletin® Version 3.8.3
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.
The contents of this forum are to be used ONLY by readers of the Learning From Data book by Yaser S. Abu-Mostafa, Malik Magdon-Ismail, and Hsuan-Tien Lin, and participants in the Learning From Data MOOC by Yaser S. Abu-Mostafa. No part of these contents is to be communicated or made accessible to ANY other person or entity.