Improve result on Ohsumed

[DiMarzioBian]

Hi, I am re-implementing this model these days and during doing that I took some of your code as referenced. I found that your code did not doing well on Ohsumed. I tried add a layer-normalization layer after embedding with input x and neibors of x, and get around 64% accuracy. Please check the project 'https://github.com/DiMarzioRock7/TextLevelGNN'.

Thank you for your codes and hope my idea solve your problem on Ohsumed dataset.

[yenhao]

That's cool! I'll look into it. Thanks for your suggestion!