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--- c:ps1:2025:t-test_note:code01 [2025/12/02 23:34] – created hkimscil
+++ c:ps1:2025:t-test_note:code01 [2025/12/02 23:51] (current) – hkimscil
@@ Line 53: / Line 53: @@
 </code>
+<code>
+#
+s.n <- 100
+s.hi <- 5200
+s.lo <- 4980
+s.sd <- 500
+set.seed(101)
+s.hi <- round(rnorm(s.n, s.hi, s.sd))
+s.lo <- round(rnorm(s.n, s.lo, s.sd))
+s.hi
+s.lo
+df.a <- s.n - 1
+df.b <- s.n - 1
+m.a <- mean(s.hi)
+m.b <- mean(s.lo)
+diff <- m.a - m.b
+pv <- (ss(s.hi)+ss(s.lo))/(df.a + df.b)
+pv
+se <- sqrt(pv/s.n + pv/s.n)
+se
+diff
+t.cal <- diff / se
+t.cal
+pt(t.cal, df.a+df.b, lower.tail = F)*2
+t.test(s.hi, s.lo, var.equal=T)
+</code>