Cognitive Constraints on How Economic Rewards Affect CooperationEllen E. Furlong and John E. Opfer · Psychological Science · 2009

Representational change and children’s numerical estimationJohn E. Opfer; Robert S. Siegler · 2007

Cognitive Constraints on How Economic Rewards Affect CooperationFurlong, Ellen E.; Opfer, John E. · Psychological Science · 2009

Dynamics and development in number-to-space mappingKim, Dan; Opfer, John E. · Cognitive Psychology · 2018

Causal relations drive young children’s induction, naming, and categorizationJohn E. Opfer; Megan J. Bulloch · 2007

The powers of noise-fitting: reply to Barth and PaladinoJohn E. Opfer; Robert S. Siegler; Christopher J. Young · 2011

Cognitive foundations for science assessment design: Knowing what students know about evolutionJohn E. Opfer; Ross H. Nehm; Minsu Ha · 2012

The Development of Numerical Estimation: Evidence for Multiple Representations of Numerical QuantityRobert S. Siegler and John E. Opfer · Psychological Science · 2003