Dimensional analysis, also known as the factor-label method, is a problem-solving technique used for comparing site costs in inventory control by considering both tangible and intangible costs. The approach involves calculating relative merits of different sites using cost ratios and weighted factors to aid in site selection for new factories and facilities. The Brown & Gibson model further elaborates on location factors by categorizing them into critical, objective, and subjective measures, ensuring site selection considers both measurable and qualitative aspects.