A method for a computer system includes receiving global positional data associated with a set of markers from a plurality of markers associated with a surface of an object at one or more time instances, wherein global positional data associated with a first marker from the plurality of markers is absent from a first time instance, using local statistical methods to determine global positional data associated with the first marker at the first time instance in response to the global positional data associated with the set of markers at the one or more time instances, and determining a model of the object in response to the global positional data associated with the set of markers and the global positional data associated with the first marker.