The Globe and Mail reports in its Wednesday edition that the late Nobel Prize-winning economist Robert Solow famously said that the effects of the personal-computer revolution can be seen everywhere -- except in the productivity statistics. Guest columnist George Athanassako writes that this is known as the Solow Paradox. No matter how overvalued a stock is, an analyst can always be found to say it is undervalued relative to another more overvalued stock. For example, one analyst set a price target for SpaceX (now $171.92 (U.S.)) of $800 (U.S.). Celebrity fund manager Cathie Wood has argued that SpaceX looks like a deep-value opportunity. Her valuation relies on two variables: how many Starship flights per year SpaceX can achieve, and how much revenue each flight can support once Starship is fully reusable. Ms. Wood extrapolated from comments chief executive officer Elon Musk made about launch occurrences and payload targets to arrive at a highly speculative annual revenue number large enough to make today's price look cheap. There is a rabble of amateur and ill-informed retail speculators betting on the basis of rumours and tip sheets. For many of them, trading has become a social act rather than a financial one.