SrTovuT & Boas: STATISTICAL STUDIES IN CICHORIUM 381 
It is obvious from such typical data as have been presented in 
the foregoing tables that the average flower number for any 
particular day (o, for ta, for example) involves the actual flower 
number on the first day of bloom plus the amount of change, 
either positive or negative, following that date. In respect to 
flower number in chicory the change is usually a decrease, and 
if this decrease be computed it can be expressed as a rate of 
chanze for the season and designated as the value 6. The 
amount of change from the first day of bloom to any one particular 
day (after the plant has been in bloom 2, days for example) сап be 
expressed by the number of days the plant has been in flower 
multiplied by the rate of change, as 04. According to this con- 
ception then o, = a + bt,, and the following series of linear equa- 
tions will express the series of averages obtained from the actual 
observations day by day: оо = a + дю... On = а + bh. 
From the data the average of the flower number obtained 
from day to day can readily be determined. This value for the 
data collected for the plant E; (see TABLE 1) arranged in the first 
column of TABLE 16 is 18.6. 
The values of ¢ are also known апа can be expressed as devia- 
tions from the average time of blooming computed from the known 
dates of the collection of data. This average as given for plant 
E; in the second column of TABLE 16 is 30.7. Since this average is 
often a fraction the calculation may be simplified by measuring 
the different times of the collection of data from the integer 
nearest to the average so that 1, = t + т, when # is the integer 
nearest the average and т, is the deviation of 2, from this integer. 
If the difference between the true average and the integer used in 
the calculation be considered as d then the full value for the devia- 
tion from the true average is 7, + d. 
The average of all the (т + d)'s must, of course, equal zero, 
because they express the plus and minus deviations from the true 
average. The average of all the 7's equals —d. The equations 
then assume the form: 
о — à +0 (t -- d + то) 
0; — a 4- b (t 4- d + т) 
Оо — à + b (t + + т) 
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