No. As written in another comment, imagine trying to determine whether two brands of cake mixes have the same density by weighing them. If you always weigh one

No. As written in another comment, imagine trying to determine whether two brands of cake mixes have the same density by weighing them. If you always weigh one of the brands with a glass bowl, but the other one with a steel bowl, you'll get enormously high units of sigma, but in reality you've only proven that steel is heavier than glass.