Geneva, Switzerland - 13 Dec - 16 Dec 2018 The ESMO Immuno-Oncology Congress, page-42

If there is of a chance of a sell off, there will be one. That might take you awhile to understand but it's the best way I can explain it. 

If results are delayed some people won't wait to see what others are doing, they will sell. Then the ones that were thinking about it see the selling which triggers them to hit the sell button. Then the technical guys assist the trend.

When price drops without negative news, this is usually a good time to go against the crowd and buy. When the price goes up after positive news a good time to sell. 
 
If you are an amateur do the opposite of what you think you should be doing and you might end up trading like a pro. 

Queue Slick...