How to increase number of outliers in a dataset?

I have a dataset with 1000 rows and 4 columns with 3 outliers .I want to add another 7 outliers related to them for detection by clustering.

     Example TO What I did
Col1 col2 Col3 col4
Out1 a1    b1   c1   d1
Out2 a2    b2   c2   d2
Out3 a3    b3   c3   d3


I get mean and std for 7 columns of normal data ten calculate

Out4  normal1+mean+stdcol1   norm1mean+stdcol2
Out5  normal2+mean+stdcol1  norm2mean+stdcol2
Out6 ...........


I don't know if what i did is right or a good solution?

I don't want outliers to be so easy for detection

Thanks

• Add an extreme number, that's it. As simple as that. – Jack Daniel May 5 at 4:35
• I don't want them to be so easy for detection – User May 5 at 4:41
• Build a Generative Model on Outliers. This model will generate new outliers which will be similar to the actual outliers with the pattern. – Jack Daniel May 5 at 7:22