Structured values are used when the value of a property has a more complex structure than simply being a textual value or a reference to another thing.
{
"@type": "olf:CompletionTimeEstimate",
"olf:enrollmentIntensity": "olf:FullTime",
"olf:typicalDuration": "P18M"
}The example feed doesn't use this term, so this snippet shows how it would look.