Differences

This shows you the differences between two versions of the page.

--- gradient_descent:code01 [2025/12/18 18:51] – hkimscil
+++ gradient_descent:code01 [2025/12/18 19:04] (current) – hkimscil
@@ Line 5: / Line 5: @@
 library(ggpmisc)
-rm(list=ls())
+# data preparation
-# set.seed(191)
+set.seed(101)
-nx <- 200
+nx <- 50 # variable x, sample size
-mx <- 4.5
+mx <- 4.5 # mean of x
-sdx <- mx * 0.56
+sdx <- mx * 0.56  # sd of x
-x <- rnorm(nx, mx, sdx)
+x <- rnorm(nx, mx, sdx) # generating x
-slp <- 12
+slp <- 4 # slop of x = coefficient, b
-y <-  slp * x + rnorm(nx, 0, slp*sdx*3)
+# y variable
+y <-  slp * x + rnorm(nx, 0, slp*3*sdx)
 data <- data.frame(x, y)
+head(data)
+# check with regression
 mo <- lm(y ~ x, data = data)
 summary(mo)
+# graph
 ggplot(data = data, aes(x = x, y = y)) +
   geom_point() +
@@ Line 24: / Line 28: @@
   stat_poly_eq(use_label(c("eq", "R2"))) +
   theme_classic()
-# set.seed(191)
 # Initialize random betas
 # 우선 b를 고정하고 a만