Motivated reasoning posits that people distort how they process  information in the direction of beliefs they find  attractive. This paper creates a novel experimental design to identify motivated reasoning from Bayesian updating when people enter into the experiment with endogenously different beliefs. It analyzes how subjects assess the veracity of information sources that tell them the median of their belief distribution is too high or too low. A Bayesian would infer nothing about the source veracity from this message, but a motivated reasoner would believe the source were more truthful when it reports the direction that he is more motivated to believe. Experimental results show  evidence for politically-motivated reasoning about immigration, income mobility, crime, racial discrimination, gender, climate change, and gun laws . Motivated reasoning from these messages leads people's beliefs to become more polarized and less accurate, even though the messages are uninformative.
Motivated reasoning posits that people distort how they process new information in the direction of beliefs they find more attractive. This paper creates a novel experimental design to identify motivated reasoning from Bayesian updating when people enter into the experiment with endogenously different beliefs. It analyzes how subjects assess the veracity of information sources that tell them the median of their belief distribution is too high or too low. A Bayesian would infer nothing about the source veracity from this message, but a motivated reasoner would believe the source were more truthful when it reports the direction that he is more motivated to believe. Experimental results show novel evidence for politically-motivated reasoning about immigration, income mobility, crime, racial discrimination, gender, climate change, gun laws, and the performance of other subjects . Motivated reasoning from messages on these topics leads people's beliefs to become more polarized and less accurate, even though the messages are uninformative.
A
new
A
more
A
novel
R
and gun laws
gun laws, and the performance of other subjects
R
these messages
messages on these topics