Regarding the anchor-text api, there is no definition for *imr on the wiki:
http://apiwiki.seomoz.org/w/page/13991127/Anchor Text API
ie.
returns "[{"apuimr":5.422834471373288e-12},{"apuimr":4.785130890652429e-13},{"apuimr":2.922901387480201e-09}]"
What is *imr?