How do Hollywood Studios or Producers get the people`s reaction for their under production or completed movie?

Question

Movie business is risky business. Stakes are very high. You can make tonns of money or lose everything you had put in thus making you a pauper. How do the producers/ directors get the feed back from paople for their under production or completed movie before release. Only if they get authentic reactions before release or under production, then only they can take the corrective measures.
Are there professional agencies in Hollywood who undertake this study? At what stages feed back is obtained? What is the procedure involved? How is the secrecy maintained? Do they give peoples reaction to the story also?

Answer 1

They use 'Test Audiences' to determine if any changes need to be made before official release. Universal picks test audiences at its Universal Studios Theme Park in FL. So does Disney. Sometimes they'll show a pre-release to an audience at a random movie theatre disguised as a 'Sneak Peak' because they want the feedback to see what (if any) changes should be made. great question!