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.
Remember, if all those sale prices disappear in a single day, that's it, they are gone. The airline is not going to put up a fresh supply of cheap seats to meet the demand. It just doesn't work that way. 4. Certain days (and times) are cheaper to fly than others.