.■trri.ic.rm)X or sr.tiisric.ti. Mr.riions 



79 



poiioiits as in tlie alH>\e pr()l)lrm. In our c.isi- the suhj^roups corre- 

 spond to tlitTerent kinds of rarhon. Here, as in the data given by 

 Pearson, it often has Inx-n foiiiui necess;»ry to base our linai conehision 

 partly up<in facts not revealed by the data tlieinselves. 



The integral curves corresponding to the normal and observed 

 distributions are given in I"ig. 10 in order to show llial llu-\ do not 



Fig. 11 



serve to indicate the difference between the obser\ed and theoretical 

 distributions nearly as well as the actual frequency curves also given 

 in this figure. Fig. 11 presents the result on probability paper. In 

 this case the probability curves are as good as the frequency curves 

 for showing the divergence between theory and observation. It will 

 Ik; recalled that this is not true for the similar cur\es gi\en in Fig. !). 



St MMARV STATICMICNT OI-' SUG(iESTKD MKTIlon TO HlC Foi.I.OWKD IN 



THE An\i,vsisof Encixeerint. .\nd Physical Data 



We have briefly re\ iewed the difTerent methods for determining 

 the best theoretical distribution to represent observed data. The 

 following four steps indicate the ordinary procedure: 



1. Obtain the first four corrected moments. 



2. Calculate the average, standard deviation, k anil ti-. and their 

 standard deviations. 



3. Calculate the the<jretical distribution of distributions warranted 

 by the circumstances. 



