How to test the default NLTK NER chunker's accuracy on own corpus?
Read in the chunked portion of your corpus and convert it into the format that the NLTK expects, i.e. as a list of shallow Trees. Once you have it in this form, you can pass it to the evaluate() method just like you would pass the "gold standard" examples. 
The evaluate method will strip off the chunks, run your text through the chunker, and compare the result with the chunks you supplied to calculate accuracy.
How to test the default NLTK NER chunker's accuracy on own corpus?
I've tagged a percentage of my own corpus. I'm curious if it's possible to use the default NLTK tagger to see accuracy rate on this corpus? 
I already know about the ne_chunker.evaluate() function, but it's not immediately clear to me how to input in my own corpus for evaluation (rather than the gold standard corpus)