Quantitative applications in the social sciences : Edited by John L. Sullivan. London, Beverly Hills: Sage Publications. No. 15. Multiple indicators, by J.L. Sullivan and S. Feldman; No. 16. Exploratory data analysis, by F. Hartwig and B.E. Dearing; No. 17. Reliability and validity assessment, by E.G. Carmines and R.A. Zeller; No. 18. Analyzing panel data, by G.B. Markus. Each title $3.00.