1. A method for operating a memory cell collection, the memory cell collection including a plurality of memory cells, each memory cell in the memory cell collection storing at least two possible binary values delimited by preset value ranges of a characteristic parameter, wherein the value ranges of the characteristic parameter shift over time, the method comprising: sensing a shifted value of the characteristic parameter for a target memory cell; sensing shifted values of the characteristic parameter for each memory cell in the memory cell collection; generating a probability distribution function of the characteristic parameter for each of the possible binary values from the shifted values of the characteristic parameter for each memory cell in the memory cell collection; for each of the possible binary values, determining a probability that the shifted value of the characteristic parameter for the target memory cell is within its probability distribution function; and converting the shifted value of the characteristic parameter for the target memory cell into a binary value for which the probability is highest.