Time series

library(readxl)
library(ggplot2)
library(tseries)

data_mentah <- read_excel("E:/KULIAH/ANALISIS RUNTUN WAKTU/data mentah.xlsx")
print(data_mentah)

## # A tibble: 104 x 2
##    Week                Transactions
##    <dttm>                     <dbl>
##  1 2016-01-04 00:00:00         9.8 
##  2 2016-01-11 00:00:00         9   
##  3 2016-01-18 00:00:00         7.68
##  4 2016-01-25 00:00:00        10.1 
##  5 2016-02-01 00:00:00         8.32
##  6 2016-02-08 00:00:00         8   
##  7 2016-02-15 00:00:00         9.8 
##  8 2016-02-22 00:00:00         8.91
##  9 2016-02-29 00:00:00         8   
## 10 2016-03-07 00:00:00        10.4 
## # ... with 94 more rows

plot(data_mentah)

y= t(data_mentah)
colnames(y) = y[1,]
y= y[-1,] 
x = ts(y, frequency = 1)

plot(x)

acf(data_mentah$Transactions)

adf.test(x)

## 
##  Augmented Dickey-Fuller Test
## 
## data:  x
## Dickey-Fuller = -0.53666, Lag order = 4, p-value = 0.9787
## alternative hypothesis: stationary