noun🔗Share协方差, 共变异数 A statistical measure defined as \scriptstyle\operatorname{Cov}(X, Y) = \operatorname{E}((X - \mu) (Y - \nu)) given two real-valued random variables X and Y, with expected values \scriptstyle E(X),=,\mu and \scriptstyle E(Y),=,\nu."The positive covariance between study time and exam scores suggests that students who study more tend to get higher scores. "学习时间和考试分数之间存在正的协方差,这表明学习时间越长的学生,往往考试分数也越高。statisticsmathscienceChat with AIVocabulary GamePractice Reading
noun🔗Share类型收窄,类型转换。 The conversion of data types from wider to narrower in certain situations."The covariance in the database system, automatically changing a double-precision number (like 3.14159) to an integer (like 3) when storing someone's age, resulted in a loss of precision but saved storage space. "数据库系统中的类型收窄(covariance),例如在存储年龄时,自动将双精度浮点数(如3.14159)转换为整数(如3),虽然损失了精度,但节省了存储空间。statisticsmathbusinessChat with AIVocabulary GamePractice Reading