All questions are good questions @Jimmy - Those companies are sorted into how much (as a dollar value) of each company is held across the Strawman membership. So, not how many people hold it, but how much of the company is held by people. As an example, the first company on the list, XRF Scientific, is popular and is held by 41 Premium members, the company ranked 3rd (AD8) is held by 71 members and #4 (AVA) is held by 86 members. However, at #2 is Liontown Resources, which is only held by 7 members. And if you click on Liontown (the company name in that list), and go to the LTR homepage, you'll see 4 options near the top of the screen ("Reports", "My Report", "Forum" and "Investors"). Click on "Investors" and you'll get the list of those 7 investors. Well, actually, my computer is only listing 6 of them. If you click on the first one ( @SFrancis ) - you'll get their homepage (see here: SFrancis profile (strawman.com)) and you will see that they only hold two positions in their portfolio and the large one is LTR, which has a current value of over $500,000.00 ($500K). The other 5 members hold the following amounts of LTR (approx.): $35K, $28K, $14K, $14K and $4K.
It is that large (over $500K) position that SFrancis holds that has propelled LTR up the "Popular" rankings.
In summary, with the "Most Popular" list, the system simply adds up the dollar value of all of the positions in that company across the entire membership ("Pro" membership if you have chosen that, otherwise the free-site membership) and then ranks them by dollar value, from largest to smallest. The two ways that companies can rise up that list is (a) if a lot of people hold that company in their portfolios, or (b) if there are one or more very large positions in that company held by a few members.