Date: June 8 2020
Summary: A critique of possible reasons for why the Spacing Effect is not applied in American educational settings.
Keywords: ##bibliography #spacing #effect #critique #education #system #archive
F. N. Dempster, "A Case Study in the Failure to Apply the Results of Psychological Research," American Psychologist, p. 8, 1988.
The spacing effect has not been studied in recent years
The spacing effect is still relatively new
The spacing effect does not have any thing to do with current issues educators face.
The spacing effect has yet to be shown well in school activities.
There are gaps in literature about the spacing effect
School-based studies do not show the spacing effect.
The spacing effect has not been well demonstrated in a classroom setting
Not enough is known about practical class implementation to warrant application of the spacing effect
The spacing effect is not well comprehended
These are the most concerning issues concerning usage of the spacing effect:
Ahistorical character of research on the spacing effect
Some failures to obtain the effect with school-like activities
Paucity of impressive classroom demonstrations of the phenomenon
Limited knowledge of classroom practice
Incomplete understanding of the psychological bases of the spacing effect
Probably the most legitimate barrier to utilization of the spacing effect in educational settings is the scarcity of in class demonstrations of its usage.
However, these four issues are not considered as such strong impediments to the implementation of the spacing effect in classroom settings:
Is not new and has been studied
Continues to receive recent documentation
Can assist in addressing educational issues
Is demonstrated to lend itself well to school-like activities
Lag effects are believed to occur when performance on a memory task improves as the number of intervening items between successive presentations increases.
Jost's Law: If two memories are equal in how well they were learned but at differing times, the older memory will gain more out of a review than the new one. 
Zelko, Jacob. A Case Study in the Failure to Apply the Results of Psychological Research. https://jacobzelko.com/06082020234244-dempster-critique. June 8 2020.
 J. A. McGeoch, “The psychology of human learning.” 1942.