Outliers Definition

1 1 6 13 13 14 14 14 15 15 16 18 18 18 19

IQR = Q3 - Q1 = 18 - 13 = 5

Q1 - 1.5 * IQR > outliers > Q3 + 1.5 * IQR

Q1 outlier = 13 - (1.5 * 5) = 5.5

Q3 outlier = 18 + 1.5 * 5 = 25.5

so the two one's are outliers.