Knowledge Base

Analyzing Observations Containing Multiple Event Logs

An observation can have multiple event logs if you imported observational data into it, for example FaceReader states. Choose how to analyze the event logs:

• Event logs as separate data sets, so each event log produces one result.
• Event logs as one data set, so all event logs within an observation are collapsed into one result.

Event Logs as Separate Data Sets

1. Click the Layout button on the Analysis toolbar.
2. Make sure that both Observations and Event Logs are selected.

The statistics are calculated as follows:

If you have not defined intervals and time bins in your data profile:

• Analyzed Duration – The duration of each event log. If the imported event log has an offset compared to the Observer XT event log, it will be shorter, since the stop of the observation determines the end of both event logs.
• Total Number and Duration Statistics – These are calculated per event log.
• Rate Per Minute (Observation Duration), Percentage (Observation Duration) – These are based on the duration of the corresponding event log.
• Rate Per Minute (Analyzed Observation Duration), Percentage (Analyzed Observation Duration) – These are based on the event log duration, excluding the suspend time.

If you have defined intervals or time bins in your data profile:

• Total Number and Duration Statistics – They are calculated per interval and event log.
• Rate Per Minute (Interval Duration), Percentage (Interval Duration) – These are based on the duration of the interval.
• Rate Per Minute (Analyzed Observation Duration), Percentage (Analyzed Observation Duration) – These are based on the duration of the event log, excluding the time that the observation was suspended.
• Rate Per Minute (Analyzed Interval Duration), Percentage (Analyzed Interval Duration) – These are based on the time line set by data selection, excluding the time that the observation was suspended. The duration of the interval is not necessarily the same as the analyzed duration, for example when two or more separate intervals split the event log into different sections. To analyze each interval separately, select the check box in front of Intervals in the Layout window.
• Percentage (Interval Duration) – This is calculated over the entire duration of the interval, not the part of the event log falling within the interval. This may give unexpected results when the event log does not cover the entire interval duration. If you want to calculate the percentage relative to the event log only, select a different type of interval (for example by selecting intervals by behavior) or use Percentage (observation duration).

Event Logs as One Data Set

1. Click the Layout button on the Analysis toolbar.
2. Make sure that Observations is selected and Event Logs is not selected.

If you have not defined intervals and time bins in your data profile:

• Analyzed Duration – The duration of the Observer XT event log.
• Total Number and Duration Statistics – They are calculated per event log, then summed up.
• Rate Per Minute (Observation Duration), Percentage (Observation Duration) – These are based on the time from the earliest start of any event log to the latest stop of any event log.
• Rate Per Minute (Analyzed Observation Duration), Percentage (Analyzed Observation Duration) – These are based on the time from the earliest start of any event log to the latest stop of any event log, excluding the time the observation was suspended.

If you have defined intervals or time bins in your data profile:

• Total Number and Duration Statistics – They are calculated per interval and event log, then summed up.
• Rate Per Minute (Interval Duration), Percentage (Interval Duration) – These are based on the summed duration of the intervals. To analyze each interval separately, keep Intervals selected in the Layout page of your Analysis settings.
• Percentage (Interval Duration) – This is calculated over the entire duration of the interval, not the part of the event log falling within the interval. This may give unexpected results when the event log does not cover the entire interval duration. If you want to calculate the percentage relative to the event log only, define an interval that only includes the event log.
• Rate Per Minute (Analyzed Observation Duration), Percentage (Analyzed Observation Duration) – These are based on the time from the earliest start of any event log to the latest stop of any event log, excluding the time the observation was suspended.
• Rate Per Minute (Analyzed Interval Duration), Percentage (Analyzed Interval Duration) – These are based on the time from the earliest start of any event log to the latest stop of any event log, excluding the time the observation was suspended and the time excluded by data selection. If overlapping event logs generate overlapping intervals, these are merged along the time line to calculate the analyzed duration. To analyze each interval separately, select the check box in front of Intervals in the Layout page of your Analysis settings.

Source: The Observer XT 17 Help - Calculate Statistics, Noldus Information Technology