Red data books seem to be a data book about endangered species common to a specific area. The reference I have listed for you below is about a Russian red data book, detailing species located in various parts of Russia that are either on the endangered list, about to be extinct, or are recently extinct. Red data books provide much information on the species contained within them, and can be a valuable source of information if you are writing a paper on a particular species that is native to that part of the world.
Outside of that, a red data book would be, perhaps a laboratory notebook one would use to write down data obtained from the execution of experiments. One would record the data, then use the data to analyze the general trend of the experiment. From these general trends, one would arrive at the conclusion of the experiment, which would be stated "In conclusion, based upon the data collected, my hypothesis was indeed correct (or not correct)..."