See Retention Time Recomputing principles if needed.

1. Select the User context for which you want to recompute retention time
2. Go to the MS Identifications→Context→Algorithms→Retention Time Recomputing to display settings dialog
3. Change algo settings options (see below) if needed and click the Ok button

On top of the dialog, is displayed the User context to process.

Retention Time Alignment panel

Outliers panel

• Don't take into account outliers: check this box if you want the algorithm to skip final outliers species (based on Grubbs)

Computing Method panel

• Average: use average to compute the parent species RT from final child species RTs
• Median: use median to compute the parent species RT from final child species RTs
• Weighted average (by score): use average weighted by score to compute the parent species RT from final child species RTs
• Best score per identification + average: from final child species, take for each identification the RT of the best score species then use average to compute the parent species RT
• Best score per identification + median: from final child species, take for each identification the RT of the best score species then use median to compute the parent species RT

Performance panel

• Use memory tuning: if NOT selected, the process will be faster but memory consuming. If selected, the process will be a little bit slower but memory efficient.