定量资料是指像身高、体重、血压等有实际意义的一些资料,这类资料的单位具有很明确的实际意义,如身高170 cm,血压140 mm Hg等。定量资料主要包括两大类,一是连续型资料,二是离散型资料。连续型资料可以取任意值,数值可以有小数点,如体质量71.6 kg;离散型资料没有小数点,只能取整数,如生存时间168 d,发病人数21人等。不管是连续型资料还是离散型资料,它们的数 Quantitative data refers to something of practical significance such as height, weight and blood pressure. Units of such data have very clear practical significance, such as height 170 cm and blood pressure 140 mm Hg. Quantitative data mainly includes two categories, one is continuous data, the second is discrete data. Continuous data can take any value, the value can have a decimal point, such as body mass 71.6 kg; discrete data without decimal point, can only take an integer, such as the survival time of 168 days, the number of 21 patients. Whether it is continuous data or discrete data, the number of them