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You can tell IGB to show you either the data above the threshold ( > thresh) or below the threshold (<= thresh). For example, for expression results graph score represents the level of hybridization activity. For a hybridization activity level to be considered significant, the score must be above a certain threshold. So you would choose the > thresh option and set your desired threshold value. If you need help to pick a threshold level, toggle the Y-axis on to see the graph's scale on the Y-axis. See Changing graph appearance Graph.
Changing the threshold
To change the thresholds of selected graphs so that more or fewer points meet the threshold limit, modify these settings in the Graph Thresholds window:
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