Prefi 



ace 



THIS BOOK HAS BEEN DEVELOPED TO PROVIDE THE BASIS OF AN 



introductory course in probability and statistics for the college and 

 university student. It includes material which has been tried out in 

 many classes and by several instructors for almost a decade. 



The instructor using the book as a text or the student interested 

 in the subject will find that college algebra is a necessary and suffi- 

 cient prerequisite for this course, which aims to teach modern but ele- 

 mentary ideas, methods of reasoning, and methods of analysis funda- 

 mental but not peculiar to any particular specialized field. Once the 

 student has acquired a background of elementary methods, prob- 

 ability, and frequency distributions, he can be taught some of the 

 simpler sampling statistics in common use today. Thus, he may 

 learn their importance as well as their application. The serious stu- 

 dent will find included in this book problems to provoke thought and 

 provide practice in statistical methods and reasoning. 



Some colleges and universities offer statistics courses — often with 

 graduate credit — in which the elementary concepts and methods are 

 not assumed to be known and hence are taught during the first part 

 of the course. It seems to me that one general course in probability 

 and statistics, with emphasis on statistical reasoning and modern 

 methods, helps to avoid useless duplication of instruction. It also 

 leaves time in subsequent courses to do more advanced work in spe- 

 cialized fields. Such an introductory course also is rapidly becoming 

 a necessary part of a student's education even if he does not use sta- 

 tistics directly in his specialized field. 



It is helpful to the students during the studies of sampling to pro- 

 vide them with some mathematical models of populations so that they 

 can obtain sampling experiences which — for a whole class — empirically 

 verify for them the sampling distributions given in some of the tables 

 which they will be using. It has been my experience that most stu- 

 dents need this sort of empirical evidence before they really under- 

 stand the nature and the use of sampling distributions. Numbers, 

 and other symbols, written on plastic discs can be made to correspond 

 closely to normal, non-normal, and binomial populations which are 



