A researcher is interested in whether certain memory strategies help people to remember information. This researcher employs students from a local college, and then randomly assigns them to one of three groupsthe visualization group, the mnemonic technique group, and the rote repetition group. Participants in each group receive an hour of instruction regarding how to use the particular technique to remember lists of words. After the instruction, all participants are presented with a list of 60 words that they are instructed to remember. The words are presented one-at-a time on a computer screen. After the last word is presented, all participants are instructed to recall as many words as possible by writing them on a blank sheet of paper. All participants are given 10 minutes to recall the words.

What are the dependent and independent variables and their levels of measurement?