user10502: Since these exchanges run 24/7, are the posted close prices (say if the chart shows 1 hour increments like on bitcoinwisdom.com) based on the last trade for that time frame?  Or are they averaged over that time frame?

user1307: They are the endpoints. You can easily see that because in a bar chart, the bars always align with either the top or the bottom of the previous bar. 

10502: <p>Since these exchanges run 24/7, are the posted close prices (say if the chart shows 1 hour increments like on bitcoinwisdom.com) based on the last trade for that time frame?  Or are they averaged over that time frame?</p>
 1307: <p>They are the endpoints. You can easily see that because in a bar chart, the bars always align with either the top or the bottom of the previous bar. </p>
