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--- summary_of_hypothesis_testing [2024/12/02 08:42] – created hkimscil
+++ summary_of_hypothesis_testing [2024/12/02 08:56] (current) – hkimscil
@@ Line 109: / Line 109: @@
 data.frame(cbind(sss, ses, lower.s2, upper.s2))
-n <- 200
+# 12/2 lecture
+# note that we draw the statistical calculation
+# by "diff/se" = "diff/random_error"
+n <- 80
 mean.sample <- 103
-diff <- mean.sample - mean.ajstu
-se <- sd.ajstu / sqrt(n)
+sample <- rnorm2(n, mean.sample, sd.ajstu)
-diff/se
+mean(sample)
+sd(sample)
+diff <- mean.sample - mean.ajstu # this is actual difference
+se <- sd.ajstu / sqrt(n) # this is random error
+t.cal <- diff/se
+t.cal
 qnorm(0.025, lower.tail = F)
 qnorm(0.01/2, lower.tail = F)
+qt(0.05/2, n-1, lower.tail=F)
+t.test(sample, mu=mean.ajstu)
+# or we obtain the exact p value
+p.value <- pt(t.cal, n-1, lower.tail = F)
+p.value*2
 </code>