adf.test(yts)
Augmented Dickey-Fuller Test
data: yts
Dickey-Fuller = -1.4222, Lag order = 3, p-value = 0.8054
alternative hypothesis: stationary
ndiffs(yts)
[1] 0
Box.test(yts,type = "Ljung-Box")
Box-Ljung test
data: yts
X-squared = 8.4516, df = 1, p-value = 0.003647