Judd, Charles M. <br/><br/>
Estimating the effects of social interventions / 
Charles M. Judd and David A. Kenny 
 - Cambridge :  Cambridge University Press,  1981 
 - 243 p. ;  23 cm. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Social science research--United States<br/>Evaluation research (Social action programs)--United States