double-blind study - an experimental procedure in which neither the subjects of the experiment nor the persons administering the experiment know the critical aspects of the experiment; a double-blind procedure is used to guard against both experimenter bias and placebo effects.
No they get more expensive, airlines will always advise you to book in advance to take advantage of their best fares. Sometimes they do a special deal but not within a week of flying. I would try another airline or make different plans.
the answer is domestic flights are at their cheapest 54 days before takeoff which could save travellers up to Â£ 190 while the worst time to book a cheap flight is last minute with the day before departure the most expensive the next biggest mistake travellers make when looking to book cheap flights is buying them too far in advance according to the findings based on travel throughout the us