Why some small coins rise in price for 10%-20% in a day WITHOUT any news?

I am trying to analyze what causes some coins to rise in price more than 10% in one day, while no announces actually happen.

1. It does not look like a pump and dump, since the price is growing gradually during the day, not in one minute and not dumping quickly.
   
2. There were no news on Twitter, media or coinmarketcal.

I will provide couple of examples:

1. DODOBTC - Today - 16 July
   
2. DODOBTC - 11 July
   
3. DODOBTC - 6 July
   
4. EPSBTC - 15 July

My best guess is that it has to do with some technical analysis that causes whales to start buying and this is causing some chain reaction, however this is just a guess.. Would love to hear your opinions.