CAPE Primer - What to Read to Get the Basics Quickly
After reading the materials pointed to here, you should have the foundational understanding needed to absorb any of the materials included in the Catalog."
"Common Sense on Mutual Funds" Bogle, John C., Chapter 2 'On The Nature of Returns'
What Are CAPE Ratios
(Tip: to come up to speed quickly, don't follow the links in the following primer materials.)
A CAPE Primer (of sorts) - quick review of the origins and theory behind CAPE ratios.
What Can CAPE Ratios Be Used For
To usefully forecast stock market returns and use the forecasts to make savvy investment decisions
To more effectively plan for retirement
At this point, you should be adequately grounded to dive into the Research Catalog and synthesize the materials.