Why did colonists become increasingly unhappy with the british goverment?

The biggest issues were Taxation without Representation (taxing the American people without giving them representation in Parliament or Government) and, under that, levying unfair taxes like the Stamp Tax - making people pay to get the official stamp on documents such as legal documents, magazines, newspapers, and playing cards. This resulted from the Stamp Act in Parliament. Another was the Sugar Act (which raised duties on Sugar imported from the West Indes), and the Currency Act (which banned America from issuing paper bills or credit bills). This came to a head with the Stamp Act (as mentioned above) and the Quartering Act, which ordered that American colonists had to house and feed British soldiers. These gave birth to the Sons of Liberty, a group of colonists unhappy with the unfair impositions, who started to fight back. The most influential event which helped their cause and the revolution was the Boston Massacre, where a group of soldiers opened fire on a crowd of protesters (of course, various accounts of this exist - in one of which a colonist provoked the soldiers). After the Tea Act, which gave the East India Company monopoly over American tea trade, and the Boston Tea Party (where colonists dumped tea off a ship in Boston harbour), things became more out of control, and the last straw was the so called Intolerable Acts in 1774, which outlawed town hall meetings and shut down the harbour. This led to the creation of the First Continental Congress and the beginning of the Revolution.

The british were making the colonists pay even more taxes for the king  at that time

The best sociological research method would have to be using experiments although it has some disadvantages as well