iv CONTENTS. 



(b) The Composition of Series for the Several Years. 99 



(c) The Extension of the System 101 



(d) The Computation of the Final Values 104 



III. Estimation and Testing of Finer Gradations of Intelli- 

 gence (Method of Ranks) 109 



1. The Problem , 109 



2. The Teacher's Estimation of Intelligence 116 



3. Estimated Intelligence and School Performance 127 



4. Rank-Orders of Intelligence Obtained by Tests. . . .135 



Bibliography , 147 



Appendix 1 155 



Appendix II 156 



Index . 159 



