Why we need the new in the select statement on one of them?

var runs = from sampleDataTable in db.SampleData 
                           from sampleInfoTable in db.SampleInfo
                           where sampleDataTable.SampleInfo.SampleInfoId == sampleInfoTable.SampleInfoId
                           select new {sampleDataTable.Timestamp, sampleDataTable.SampleDataId, sampleInfoTable.Lane} ;

and

var runs2 = from sampleDataTable in db.SampleData
                           from sampleInfoTable in db.SampleInfo
                           where sampleDataTable.SampleInfo.SampleInfoId == sampleInfoTable.SampleInfoId
                           && sampleDataTable.Timestamp == timestamp
                           select sampleInfoTable.Lane;