So I'm reading Python Machine Learning by Sebastian Raschka, but I'm getting a little lost on an equation that appears multiple times in the book in two different forms.

Here it is with (y) and (1-y) as indicator functions: [![enter image description here][1]][1]

It then appears in this form with the initial (y) indicator missing. Where did it go?? Is it not important? My intuition tells me it needs to stay in the equation. [![enter image description here][2]][2]

Lastly, here it is with an l2 penalty: << cannot post more than 2 links. sorry >>

Can anyone help explain this discrepancy? What am I not understanding? [1]: https://i.sstatic.net/RS4PC.png [2]: https://i.sstatic.net/mYXo3.png

So I'm reading Python Machine Learning by Sebastian Raschka, but I'm getting a little lost on an equation that appears multiple times in the book in two different forms.

Here it is with (y) and (1-y) as indicator functions:

It then appears in this form with the initial (y) indicator missing. Where did it go?? Is it not important? My intuition tells me it needs to stay in the equation.

Lastly, here it is with an l2 penalty: << cannot post more than 2 links. sorry >>

Can anyone help explain this discrepancy? What am I not understanding?