The Globe and Mail reports in its Saturday edition that index investors are facing a quandary this year after the strong rally in artificial-intelligence-related stocks left the S&P 500 dominated by a handful of massive technology companies: Do you stick with an index that looks top-heavy? The Globe's David Berman writes that traditional index investing, which generally weights companies based on market capitalization, has long held appeal. Numerous studies highlight the poor record of most actively managed mutual funds. Investing in a low-fee exchange-traded index fund is an ideal solution. However, the S&P 500 is looking a bit wacky this year, leading some observers to consider alternatives to traditional indexing. The S&P 500 gained 16.9 per cent during the first half of 2023, but the breadth of the rally was the narrowest in history for the first half of a year, according to Savita Subramanian, quant strategist at Bank of America. Blame Big Tech: The shares of the five biggest companies in the S&P 500 -- Apple, Microsoft, Alphabet, Amazon and Nvidia -- are up 75 per cent in 2023, on average. Ms. Subramanian's recommendation: Own the equal-weighted version of the index for the second half of the year.