1 # z test with known sigma, normal or large samples 2 library('BSDA') 3 x = c(159, 280, 101, 212, 224, 379, 179, 264, 222, 362, 168, 250, 4 149, 260, 485, 170); 5 z.test(x, alternative = "greater", mu=225,sigma.x=98, 6 conf.level = 0.95) 7 #标准正态分布 8 # one of "greater", "less" or "two.sided",单侧/双侧 9 # sigma.x must be known 10 11 12 # t test with unknown sigma, normal 13 # t分布检验 14 t.test(x, alternative = "greater", mu=225, conf.level = 0.95) 15 16 # two samples,z-test and t-test 17 sdx = sd(x); 18 sdy = sd(y); 19 z.test(x,y, mu=0,alternative = "less",sigma.x=sdx,sigma.y=sdy) 20 t.test(x,y,mu=0,alternative = "less",var.equal = TRUE) 21 22 23 24 # one and two samples, variance 25 library('DescTools') 26 VarTest(x,alternative="two.sided",sigma.squared=3,conf.level=0.95) 27 VarTest(x,y,alternative = "two.sided",ratio=3); 28 29 a2q 30 #non-normal 31 #prop.test can be used for testing the null that the proportions (probabilities of success) in several groups are the same, or that they equal certain given values 32 prop.test(445, 500, p = 0.85, alternative = "greater") 33 34 35 #非参数统计 36 # Nonparametric test, ks-test 37 x <- rnorm(50) 38 y <- runif(30) 39 # Do x and y come from the same distribution? 40 ks.test(x, y) 41 # Does x come from another distribution 42 ks.test(x+2, "pgamma", 3, 2) # two-sided, exact 43 ks.test(x, "pnorm") 44 ks.test(x+2, "pgamma", 3, 2, alternative = "gr") 45 46 #Nonparametric,lillie.test 47 LillieTest(rnorm(100, mean = 5, sd = 3)) 48 LillieTest(runif(100, min = 2, max = 4)) 49 50 #Nonparametric