kk匡的日記&學習筆記

/*
Simple linear regression 简单回归分析
Bar Chart、条形统计图
月薪和花红的关系。
*/

userName <- c("Lam Wei Wei", "Zheng Da Shi", "Lin Da You", "Fei Gu Man", "Chen Kuang", "Wong wei yun")
salary <- c(8500, 9800, 12500, 15000, 8700, 7500)
jobPosition <- c("Staff", "Manger", "BOSS", "CEO", "Staff", "Staff")
bonus <- c(2300, 1350, 3285, 1035, 3285, 1035)

#取得salary和bonus的图表
result <- data.frame(salary, bonus)
result

#用正态分布计算salary和bonus的方差
totalAmount.lm = lm(salary ~ bonus, data=result)
totalAmount.lm

#系数
coeffs = coefficients(totalAmount.lm); 
coeffs

#bonus是3250的话、salary会是...？
newdata = data.frame(bonus=3250)
predict(totalAmount.lm, newdata)

  salary bonus
1   8500  2300
2   9800  1350
3  12500  3285
4  15000  1035
5   8700  3285
6   7500  1035

Call:
lm(formula = salary ~ bonus, data = result)

Coefficients:
(Intercept)        bonus  
 10798.8760      -0.2273  

  (Intercept)         bonus 
10798.8759664    -0.2272787 
       1 
10060.22 

答案：salary是10060.