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userguide:retentiontimealignment [2010/08/02 11:37]
132.168.74.230
userguide:retentiontimealignment [2010/08/02 16:24]
132.168.74.230
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     - Compute one (or several) representative value(s) for group1 & group2 for each pair group     - Compute one (or several) representative value(s) for group1 & group2 for each pair group
     - Compute linear regression between representative values ​     - Compute linear regression between representative values ​
-    - Store linear regression coefficients in identification properties+    - Store linear regression coefficients ​& reference context name in identification properties
  
 ===== In more details... ===== ===== In more details... =====
  
 {{ RtAlignmentConcept1.PNG}} {{ RtAlignmentConcept1.PNG}}
-  - Species Retention Time of the reference UserContext are predicted with **NETPrediction v2.2.3378** utility using Kangas method (click [[http://​omics.pnl.gov/​software/​NETPredictionUtility.php|here]] for more details). NETPrediction utility only uses species **sequences** to predict a Normalized Elution Time (NET) value. First, a list of '//​reference//'​ species is built with the below criteria, then the corresponding sequences are exported in order to be used by the NETPrediction utility: +  - Species Retention Time of the reference UserContext are predicted with **NETPrediction v2.2.3378** utility using Kangas method (click [[http://​omics.pnl.gov/​software/​NETPredictionUtility.php|here]] for more details). NETPrediction utility only uses species **sequences** to predict a Normalized Elution Time (NET) value. ​ 
-    * The reference species list doesn'​t contain any species with PTMs +    - First, a list of '//​reference//'​ species is built 
-    * If several species exist with redundant sequences, the best score species is retained +         ​* The reference species list doesn'​t contain any species with PTMs 
-  - The predicted NET are converted to retention time. The user can decide to exclude predicted values too far from the others. It is actually based on  +         ​* If several species exist with redundant sequences, the best score species is retained 
-  - and stored as properties in the reference species. +    - Then, the corresponding sequences are exported in order to be used by the NETPrediction utility 
-  - For each identification existing under the reference User context:+  - The predicted NET are converted to retention time using user-defined parameters (duration & delay) 
 +  - The user can decide to exclude predicted values too far from the others:  
 +    * The average absolute deviation (between RT & predicted RT) is computed and all predicted RT far from this average value about a given user-defined threshold are excluded. 
 +  - The predicted RT values are then stored as properties in the reference species. 
 +  - For each identification existing under the reference User context ​(not necessary directly under the reference user context):
     -  All the final child species to align are collected     -  All the final child species to align are collected
     -  Several pair groups are created using reference species & species to align. A pair group contains 2 groups of species having same sequence & calculated mass (group1 has species from reference User context and group2 has species to align from identifications).     -  Several pair groups are created using reference species & species to align. A pair group contains 2 groups of species having same sequence & calculated mass (group1 has species from reference User context and group2 has species to align from identifications).
-  +    - For each group, according the statistical method choosen by the user, one or several representative RT value(s) is(are) calculated. 
- +      * Each '​Group1'​ always contains one species because [[userguide:​proteingroups|species/​protein grouping]] has been executed on the reference context and suppressed sequence/​calculated mass redundancy. 
- +      * '​Group2'​ may contain one or more species. One or several representative value(s) is(are) calculated from one of following statistical methods: 
- +        * Average ​{{ :userguide:rtalignmentconcept3.png|}} 
-{{:​userguide:​specif_alignement_tr_2.png|}}+        * Median 
 +        * Cross-product 
 +        * Combined 
 +        * Best score 
 +    - Compute linear regression between pair groups 
 +    - Store linear regression coefficients (slope/​intercept) + reference context name in the identification properties ​
  
  
userguide/retentiontimealignment.txt · Last modified: 2010/08/02 16:27 by 132.168.74.230