All Forums  Origin Forum  Origin Forum  Standard Errors Using Fit Linear With X Error

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

Screensize: 640 x 480 800 x 600 1024 x 768 1280 x 1024 UserName: Password: Anti-Spam Code: Format Mode: Basic  Help  Prompt  Format: Font Andale Mono Arial Arial Black Book Antiqua Century Gothic Comic Sans MS Courier New Georgia Impact Lucida Console Script MT Bold Stencil Tahoma Times New Roman Trebuchet MS Verdana   Size 1 2 3 4 5 6   Color Black Red Yellow Pink Green Orange Purple Blue Beige Brown Teal Navy Maroon LimeGreen Message: * HTML is OFF * Forum Code is ON Smilies [quote][i]Originally posted by rldc2[/i] [br]Origin Ver. and Service Release (Select Help-->About Origin): 8.1.88.89 (Academic) Operating System: Windows XP Hi, I'm attempting to fit some data with both x and y errors linearly using the 'Ripley' technique. This appears to give convincing intercept and slope values, but gives unfeasible values for the standard errors which are important for us to know. The actual data is: X XErr Y YErr --------------------------------------------- 185.01172 17.53857 542.5 201 218.15645 20.37692 830 411.5 242.4442 24.2924 761.5 63.5 306.3891 33.87535 1025 75.5 350.38988 31.47779 1202 202.5 371.85471 35.43873 1223.5 147.5 397.61866 34.50598 1197 230.5 442.85956 39.02208 1292.5 167.5 464.1512 42.77052 1291.5 94.5 520.11983 47.9279 1818 503.5 568.47473 55.99731 1982.5 213 518.55814 54.24961 1434.5 369.5 623.59091 69.87129 2246 242 721.37299 63.82286 2586 527 951.53452 95.24863 2349.5 353.5 851.85754 73.99066 2779.5 1132 628.54034 53.34334 1663.5 500 838.98543 70.65024 2714.5 601 1385.44779 166.61908 4425 1174 Which appears to give: Intercept = -5.67818 St Err = 0.02723 Slope = 3.16769 St Err = 13.27179 Which can't be right. I'm fitting via the Dialog box and using the Ripley method as the most appropriate. I can't see what I might be doing wrong, or if there is a bug with the output how to get around this (possible use of an X-function in LabTalk? fitLRXErr? But I'm not clear in syntax for this function...) Any help would be greatly appreciated. Many thanks, Robert [/quote]   Check here to include your profile signature. Check here to subscribe to this topic.