Suppose I have 100 items and I would like to come up with their ranking based on user preferences. i.e. each item should receive a rank from between 1-100, where 1 is the most preferred item and 100 is the least preferred item. Data is collected through pairwise comparisons, where users choose which item they prefer (boolean). Out of these comparison a final ranking will be determined. How do I rigorously determine the number of pairwise comparisons I need per item, to produce a "statistically significant" ranking? I am less interested in how the ranking is constructed and more interested in determining a suitable sample size, but I understand these two may be linked.