Erratum to: Does it help to use mathematically superfluous brackets when teaching the rules for the order of operations?

Abstract

The original version of this article contained an editing error towards the end of section 1. The corrected passage is given below. (2011) showed that elementary school students could gain from using emphasizing brackets. In their experiment young students (grades 2 and 3 in Italy and Greece) compared simple algebraic expressions, and emphasizing brackets improved the number of correct answers in cases such as, for example, + 4 = 9 and ( + 4) = 9. Brackets can indeed change the way in which expressions are perceived. Marchini and Papadopoulos