词汇	variance covariance
释义	variance covariance 变异数协方差
随便看	all ports block all-ports block Allport's mastoid retractor allport theory of personality allport-vernan scale of values test all position all-position all-position automatic tubesheet welding system all-position electorde all position electrode all-position electrode all position gas copying cutting machine all-position oxygen cutting machine all position pipeline automatic arc welding allposition tire all position tire allposition tyre all position tyre all-position welder all position welding all-position welding all-position welding machine all-position weld of pipeline all positioon weld all-positive vector