/s'1mIBELL'S MATHEMATICAL SERIESADVANCED SECTIONGeneral Editor-. WILLIAM P. MILNE, D.Sc.M.A.,Professor of University of Lef.dsMathematics,A FIRST COURSE IN STATISTICSSERIES.BELL'S MATHEMATICALADVANCED SECTION.Editor: WILLIAM P. D.Sc,General MILNE, M.A.,of of Leeds.Professor Mathematics, UniversityTREATISE ON DIFFEREN-AN ELEMENTARYAND THEIR APPLICA-TIAL EQUATIONSH. T. H.TIONS. PiAGGio, M.A., D.Sc,ByProfessor of Mathematics, University College,8vo. 12s.Nottingham. DemyIN NOMOGRAPHY. S.A FIRST COURSE ByB. Ph.D. Reader inM.a. Sc.Brodetsky, , , , AppliedatLeeds 8vo. lOs.Mathematics University. DemyAN INTRODUCTION TO THE STUDY OFVECTORANALYSIS. C. E.By Weatherburn,M.A. D. Sc. Professor of Mathematics and Natural, ,Ormond of Mel-College, UniversityPhilosophy,bourne. 8vo. 12s. net.DemyCOURSE IN STATISTICS. D.A FIRST ByLecturerCaradog M.A., F.S.S.,Jones, formerlyin Mathematics at Durham 8vo.University. Demynet.15s.-OF NONTHE ELEMENTS EUCLIDEANM. Y.GEOMETRY. D.By Sommerville,Professor of VictoriaM.A., D.Sc, Mathematics,N.Z. Crown 8vo.University College, Wellington,6d. net.7s.LONDON : G. BELL AND LTD.SONS,I^^\A FIRST COURSEINSTATISTICSBY.\rv-^F.S.S,D. CARADOG M.A.,JONES,FORMERLY LECTURER IN MATHEMATICSAT DURHAM UNIVERSITYLONDONLTD.G. BELL AND SONS,I192PREFACEa section of theFifty large general were notyears ago publicwe now call theuninterested in what social butproblem,only theya to the existence of such athoughtscarcely ...