The presentation is a bit weak. The intention is that all three fractional values are included within the scope of the big sigma. There ideally would be a big bracket around all the terms to show that they are inside the big sigma summation, but that level of detail is often sadly omitted.
For each step of the index dummy variable you get three fractional values. I hope this helps.
The presentation is a bit weak. The intention is that all three fractional values are included within the scope of the big sigma. There ideally would be a big bracket around all the terms to show that they are inside the big sigma summation, but that level of detail is often sadly omitted.
For each step of the index dummy variable you get three fractional values. I hope this helps.