It is more like trial and error. They make the experiment more accurate by the correct measurements and making sure they are using the correct equipment. When something goes wrong they simply repeat the experiment, to make the experiment improve.
Run it again and again, double check it again and again and have others run the same experiment.
It's difficult for a single scientist to make sure the results aren't a mistake (if the instrument used is miscalibrated, just running the experiment again may well give the same incorrect results; also, if the scientist habitually forgets to clean out the glassware from the last experiment, this could cause the results to be wrong even if the scientist uses a second instrument that is properly calibrated), but the scientific community as a whole can.
This is called "reproducibility" and is a goal for all experiments. It shouldn't matter so much who's doing the experiment or where they're doing it or who manufactured the equipment used. The important thing is that other scientists in other labs using other equipment get the same results. At that point you can be reasonably sure that the results are not a mistake ... though the interpretation still may be.
repeat the experiment
Whatever experiment scientists do, when they make a mistake they obviously need to do the whole experiment again!
To do again. Scientist repeat (do again) experiments in order to make sure the results are accurate.
Wow, You must be doing a crossword puzzle. LOL. Scientist use their data to make charts and graphs to communicate the results of an experiment. 1/29/09
There is a very rare possibility that a laboratory might make a mistake on DNA testing. These DNA tests are generally run along with positive and negative control reactions so that even if there were a mistake, it would clearly become evident before reporting the results. Given the importance of DNA evidence in a court of law, there are more than one lab working on the same sample so that consistent results can be obtained. DNA testing labs have to be audited and have their licences renewed every year. This processes eliminates error and reduces the possibility of erroneous results.
$1
fix it
redo
Experimental error.
the answer is: Error
Scientist use their data to make charts and GRAPHS to communicate the results of their experiment.
Whatever experiment scientists do, when they make a mistake they obviously need to do the whole experiment again!
error
It is simply the scientific method in action. Make a mistake, correct it and go on or start again.
It's called an error.
Error
So they know not to make the same mistake again
To make theirs better and understand it