Standard devaiton is between -2 and 2 but our goal was to have unit standard deviation?

#1

Standard deviation of the normalised dataset is between -2 and 2 but our goal was to have unit standard deviation?

#2

hey @vineetchanana ,
I guess actually the thing you wanna say is that your standardized values are in a range of -2 and 2 ? is this correct ?

Kindly let me know . If am wrong then i would request you to kindly brief more about your doubt as i am unable to understand it properly.

#3

Yes, we applied this formula on our dataset,
u = X_train.mean(axis=0)
std = X_train.std(axis=0)

X_train = (X_train - u)/std
Would it call it standardised or normalised ?
After applying this formula our dataset has mean = 0 but dataset lies in range from -2 to 2. Shouldn’t it lie in -1 to 1?

#4

hey @vineetchanana ,
yeah you have standardized your data now.
So after standardization the range would depend upon dataset but the overall standard deviation would be one. It doesn’t need your data to be in a particular range like it will not be always in -1 to 1 . But the final mean will be 0 and std will 1.

I hope you get that.

1 Like