The Origin Forum
File Exchange
Try Origin for Free
The Origin Forum
Home | Profile | Register | Active Topics | Members | Search | FAQ | Send File to Tech support
 All Forums
 Origin Forum
 Origin Forum
 compare slopes

Note: You must be registered in order to post a reply.
To register, click here. Registration is FREE!

Screensize:
UserName:
Password:
Anti-Spam Code:
Format Mode:
Format: BoldItalicizedUnderlineStrikethrough Align LeftCenteredAlign Right Horizontal Rule Insert HyperlinkUpload FileInsert Image Insert CodeInsert QuoteInsert List
   
Message:

* HTML is OFF
* Forum Code is ON
Smilies
Smile [:)] Big Smile [:D] Cool [8D] Blush [:I]
Tongue [:P] Evil [):] Wink [;)] Clown [:o)]
Black Eye [B)] Eight Ball [8] Frown [:(] Shy [8)]
Shocked [:0] Angry [:(!] Dead [xx(] Sleepy [|)]
Kisses [:X] Approve [^] Disapprove [V] Question [?]

 
Check here to subscribe to this topic.
   

T O P I C    R E V I E W
scalpa Posted - 12/09/2013 : 11:45:49 AM
Origin pro 9.0:

Hello,
i would like to compare the slopes of the linear fits of two different datasets. to be more accurate, I have two distinct data sets that I fit independently by a linear regression. I then get 2 slopes as results (I'm not interested in the intercepts) and I would like to know if these slopes are significantly different or not.

thanks !!

PSilberz
5   L A T E S T    R E P L I E S    (Newest First)
Sam Fang Posted - 12/12/2013 : 9:04:21 PM
The test is F-test. Origin's Compare Datasets tool also uses F-test.

Sam
OriginLab Technical Services
scalpa Posted - 12/12/2013 : 06:08:24 AM
I think I was not clear: following your indications, the test allows me to conclude. but I would need some background (ie the name of the test via this f distribution function). thanks,
S.
Sam Fang Posted - 12/12/2013 : 05:35:24 AM
You can send your data to us, and then we can make an analysis template for you. The problem is not complex.

To send files to us, click Send File to Tech support button in the top right of the forum.

Thanks.



Sam
OriginLab Technical Services
scalpa Posted - 12/12/2013 : 04:57:56 AM
Thanks a lot Sam,

How can I call this test if I am to describe it ?

best

scalpa
Sam Fang Posted - 12/11/2013 : 9:05:32 PM
It can be done as follows:
1. Perform Linear Fits for two data separately.
Compute the sum of two RSS(Residual Sum of Squares) and df(Degrees of Freedom), and they are denoted by RSS1, df1.
2. Share the two slopes and perform global linear fit for two data in NLFit dialog. RSS and df in the global fit are denoted by RSS2, df2.
3. Determine whether slopes are different. You can run following script in Origin's script window.

F1=(RSS2-RSS1)/(df2-df1)/(RSS1/df1);
p1=1-fcdf(F1,df2-df1,df1);


If p1<0.05, slopes are different.

We will provide a built-in tool to compare parameters in fitting in Origin's next version.

Sam
OriginLab Technical Services

The Origin Forum © 2020 Originlab Corporation Go To Top Of Page
Snitz Forums 2000