《医学统计学》 N

natality出生率natural logarithm自然对数negative correlation负相关negative skewness负偏志no correlation无相关non-linear correlation非线性相关non-parametric statistics非参数统计normal curve正态曲线normal deviate正态离差normal distribution正态分布normal population正态总体normal probability curve正态概率曲线normal range正常范围normal value正常值normal kurtosis正态峰normality test正态性检验nosometry患病率null hypothesis无效假设，检验假设