| A | absorbance for computing %reduction in bacte- rial growth from turbidimetric readings. |
| b | slope of the straight line relating response (y)to log-dose (x)[Equations 2b,4,5,6]. |
| c | constant for computingM¢with Equations 8 and 10. |
| c¢ | constant for computing Lwith Equations 26 and 29. |
| ci | constant for computingM¢when doses are spaced as in Table 8. |
| c¢i2 | constant for computing Lwhen doses are spaced as in Table 8. |
| C | term measuring precision of the slope in a confidence interval [Equations 27,28,35,36]. |
| c2 | statistical constant for testing significance of a discrepancy [Table 9]. |
| cM2 | c2testing the disagreement between different estimates of log-potency [Equations 39,40]. |
| eb | eifrom row bin Tables 6to 8. |
| eb¢i | multiple of S(x –bar(x))2[Table 5;Equation 6]. |
| ei | sum of squares of the factorial coefficients in each row of Tables 6to 8. |
| eq | eifrom row qin Tables 6to 8. |
| f | number of responses at each dosage level of a preparation;number of replicates or sets. |
| fS | number of observations on the Standard. |
| fU | number of observations on the Unknown. |
| F1to F3 | observed variance ratio with 1to 3degrees of freedom in numerator [Table 9]. |
| G1,G2,and G3 | relative gap in test for outlier [Table 1]. |
| h | number of Unknowns in a multiple assay. |
| h¢ | number of preparations in a multiple assay, including the Standard and hUnknowns;i.e., h¢=h+1. |
| i | interval in logarithms between successive log-doses,the same for both Standard and Unknown. |
| k | number of estimated log-potencies in an average [Equation 24];number of treatments or doses [Table 4;Equations 1,13,15,16];number of ranges or groups in a series [Table 2];number of rows,columns,and doses in a single Latin square [Equations 1a,16a]. |
| L | length of the confidence interval in logarithms [Equations 24,26,29,38],or in terms of a proportion of the relative potency of the dilutions compared [Equations 31,33]. |
| Lc | length of a combined confidence interval [Equations 42,43]. |
| Lc¢ | length of confidence interval for a semi-weighted mean bar(M)[Equation 48]. |
| LD50 | lethal dose killing an expected 50%of the animals under test [Equation 2c]. |
| M | log-potency [Equation 2]. |
| M¢ | log-potency of an Unknown,relative to its assumed potency. |
| bar(M) | mean log-potency. |
| n | degrees of freedom in an estimated variance s2or in the statistic tor c2. |
| n¢ | number of Latin squares with rows in common [Equations 1a,16a]. |
| N | number;e.g.,of observations in a gap test [Table 1],or of responses yin an assay [Equation 16]. |
| P | probability of observing a given result,or of the tabular value of a statistic,usually P=0.05or 0.95for confidence intervals [Tables 1,2,9]. |
| P* | potency,P*=antilog Mor computed directly. |
| R | ratio of a given dose of the Standard to the corresponding dose of the Unknown,or assumed potency of the Unknown [Equations 2,30,33]. |
| R* | ratio of largest of kranges in a series to their sum [Table 2]. |
| s =Öbar(s)2 | standard deviation of a response unit,also of a single estimated log-potency in a direct assay [Equation 24]. |
| s2 | error variance of a response unit. |
| Si | a log-dose of Standard [Tables 6,7]. |
| S | “the sum of.” |
| t | Student's tfor ndegrees of freedom and probability P=0.05[Table 9]. |
| T | total of the responses yin an assay [Equation 16]. |
| T¢ | incomplete total for an assay in randomized sets with one missing observation [Equation 1]. |
| T1 | S(y)for the animals injected with the Standard on the first day [Equations 18,36]. |
| T2 | S(y)for the animals injected with the Standard on the second day [Equations 18,36]. |
| Ta | Tifor the difference in the responses to the Standard and to the Unknown [Tables 6to 8]. |
| Tab | Tifor testing the difference in slope between Standard and Unknown [Tables 6to 8]. |
| Taq | Tifor testing opposed curvature in the curves for Standard and Unknown [Tables 6to 8]. |
| Tb | Tifor the combined slope of the dosage-response curves for Standard and Unknown [Tables 6to 8]. |
| Tb¢ | S(x1Tt)or S(x1y)for computing the slope of the log-dose response curve [Equations 10,23, 28]. |
| Ti | sum of products of Ttmultiplied by the corresponding factorial coefficients in each row of Tables 6to 8. |
| Tq | Tifor testing similar curvature in the curves for Standard and Unknown [Tables 6to 8]. |
| Tr | row or set total in an assay in randomized sets [Equation 16]. |
| Tr¢ | incomplete total for the randomized set with a missing observation in Equation 1. |
| Tt | total of fresponses yfor a given dose of a preparation [Tables 6to 8;Equations 6,13, 14,16]. |
| Tt¢ | incomplete total for the treatment with a missing observation in Equation 1. |
| Ui | a log-dose of Unknown [Tables 6to 8]. |
| v | variance for heterogeneity between assays [Equation 45]. |
| V=1/w | variance of an individual M[Equations 44to 47]. |
| w | weight assigned to the Mfor an individual assay [Equation 38],or to a probit for computing an LD50[Equations 2a,2b]. |
| w¢ | semi-weight of each Min a series of assays [Equations47,48]. |
| x | a log-dose of drug in a bioassay [Equation 5]; also the difference between two log-threshold doses in the same animal [Equation 12]. |
| x* | coefficients for computing the lowest and highest expected responses YLand YHin a log-dose response curve [Table 4;Equation 3]. |
| x1 | a factorial coefficient that is a multiple of (x –bar(x)) for computing the slope of a straight line [Table 5;Equation 6]. |
| bar(x) | mean log-dose [Equation 5]. |
| bar(x)S | mean log-dose for Standard [Equation 9]. |
| bar(x)U | mean log-dose for Unknown [Equation 9]. |
| X | log-potency from a unit response,as interpolated from a standard curve [Equations 7a,7b,19]. |
| XM | confidence limits for an estimated log-potency M
[Equations 25,30]. |
| XP* | confidence limits for a directly estimated potency P*(see Digitalisassay)[Equation 33]. |
| y | an observed individual response to a dose of drug in the units used in computing potency and the error variance [Equations13to16];a unit difference between paired responses in 2-dose assays [Equations17,18]. |
| y1...yN | observed responses listed in order of magnitude, for computing G1,G2,or G3in Table 1. |
| y¢ | replacement for a missing value [Equation 1]. |
| bar(y) | mean response in a set or assay [Equation 5]. |
| bar(y)t | mean response to a given treatment [Equations3,6]. |
| Y | a response predicted from a dosage-response relationship,often with qualifying subscripts [Equations 3to5]. |
| z | threshold dose determined directly by titration (see Digitalisassay)[Equation 11]. |
| bar(z) | mean threshold dose in a set (see Digitalisassay) [Equations 31,32,33]. |