# Side by side

Definition

The focal subject is side-by-side with another subject. The latter is named receiver in EthoVision XT.

Two categories are defined, based on how the subjects are oriented relative to one another.

▪Same direction: the focal subject and the receiver are side by side and pointing to the same direction (in the figure below, left).

▪Opposite direction: the focal subject and the receiver are side by side and pointing to the different directions (in the figure below, right).

This variable is available in experiments set to Center-point, nose-point and tail-base detection. See Tracked features

Calculation

▪For Side by side, same direction:

▪EthoVision XT finds the samples where both the distance between the nose-point of the focal subject and the nose-point of the receiver and the distance between the tail-base point of the focal subject and the tail-base point of the receiver are below the specified threshold (default: 5.26 cm).

▪If the two vectors formed by the tail-base point and the nose-point of each subjects point to the same directions (that is, the dot product of the two vectors is positive), then Side by side, same direction is scored for that sample.

▪For Side by side, opposite direction:

▪EthoVision XT finds the samples where both the distance between the nose-point of the focal subject and the tail-base point of the receiver and the distance between the tail-base point of the focal subject and the nose-point of the receiver are below the specified threshold (default: 5.26 cm).

▪If the two vectors formed by the tail-base point and the nose-point of each subjects point to opposite directions (that is, the dot product of the two vectors is negative), then Side by side, opposite direction is scored for that sample.

How to specify Side by side

1.Open an Analysis profile and in the Dependent Variables panel, under Social, click the Add button next to Side by side.

2.Under Threshold, enter the maximal In proximity distance acceptable between the two subjects’ body points (nose to nose or nose to tail-base).

3.Under Calculate statistics for, select the option Side by side, same direction, or Side by side, opposite direction, or both.

4.Complete the procedure to add the variable to the Analysis profile. See Calculate statistics: procedure

Note

Side by side is similar to Proximity, however the latter cannot tell whether the subjects are oriented in the same or different directions.

See also

▪Proximity