How do you choose what percentage to allocate to a company in your portfolio?

In your opinion, is there an objective way to determine how much to allocate to each stock in a portfolio based on parameters available online (for example, some of the data in the “Statistics” tab on stockanalysis.com)? I would like to obtain, for each company, a numerical value based both on growth potential and on financial stability, so that the differences between them are not too wide. I would then convert this value into a score from 1 to 10, which I would use to determine portfolio percentages. I tried using “EV / Adjusted EBITDA,” but I am not satisfied with it, since the data are distorted both when a company has an excessively high valuation and when it has negative EBITDA.