At 08:23 AM 7/23/02 -0700, Gordon Kenyon wrote: > I think I make it clear later in my post. What I am describing is >the density function presented to look really scary (with the number >"e" and pi and all), then hustled away never to spoken of again, its >role fulfilled by "table C". As a stand-alone density function it >isn't much use- taking the integral converts it into the distribution >function. Not that any of this is even hinted at in introductory >social/behavioral science stats texts.
moore and mccabe have in their 3rd edition of "introduction to the practice of statistics" ... page 71 ... this formula and it is presented in a number of other texts ... they go on to say: "we will not make direct use of this fact ... " (in their book ... areas to look up are in table A) are you suggesting that a typical instructor should try to work through several examples of THIS formula? now and then i have done that but ... it is a mess ... and, don't think it is worth that mess ... can't one get just as good a feeling by having a unit normal baseline ... and seeing that the height is tallest at 0? are you suggesting that the instructor should somehow .... talk about or discuss, even at a low level ... "... taking the integral converts it into the distribution function ... " ? how many students ... in intro kinds of classes ... would even know what an "integral" is? it seems to me that what you are asking for is that instructors will discuss with students HOW that formula was developed and, i would contend that is WAY beyond what is logical or practical to consider doing in an intro kind of course (maybe in some elementary course in a program in math/stat ... for math/stat majors) > One is told rather (in the >several example texts I have on hand) that further explanation >"requires calculus". I contend it is a long way from "calculus in >general" to the information that will allow a student to initiate a >sound base for her or his work. moore and mccabe don't mention "calculus" ... but, do give some examples of how that distributional shape is important in statistical kinds of work from your notes ... it is a little difficult to know precisely what it is you are "hoping" that 'texts' and 'instructors' would say to students and expect them to know > I use (and am used to) "computing >formula" meaning a directly applicable function providing a meaningful >outcome. Like one is generally provided for variances, sums of >squares and one-and-two-variable regressions. >. >. >================================================================= >Instructions for joining and leaving this list, remarks about the >problem of INAPPROPRIATE MESSAGES, and archives are available at: >. http://jse.stat.ncsu.edu/ . >================================================================= Dennis Roberts, 208 Cedar Bldg., University Park PA 16802 <Emailto: [EMAIL PROTECTED]> WWW: http://roberts.ed.psu.edu/users/droberts/drober~1.htm AC 8148632401 . . ================================================================= Instructions for joining and leaving this list, remarks about the problem of INAPPROPRIATE MESSAGES, and archives are available at: . http://jse.stat.ncsu.edu/ . =================================================================
