Not able to set lookup field value

var recordname = $("#SelectEntityPrimaryName").val();
var recordnamevalue = $("#SelectEntityPrimaryName option:selected").text();
	var primaryrecord = new Array();
	primaryrecord[0] = new Object();
	primaryrecord[0].id = recordname;
	primaryrecord[0].name = recordnamevalue;
	primaryrecord[0].entityType = "new_event";
Xrm.Page.data.entity.attributes.get("regardingobjectid").setValue(primaryrecord);