This article by G. Kärber discusses a method for collectively treating pharmacological series experiments, which has been applied at the institute for the computational recording of experimental data. The method is based on the collective measure theory, which has been extensively discussed by Trevan, Wiechowski, Behrens, and others. The key considerations in selecting a suitable computational procedure were: 1. The method should yield useful results even in cases of strong scatter in the series experiment. 2. The method should be applicable equally well to arithmetic and geometric progression of dosages. The formula used for calculations is: \[ (aM) = D_m - \sum_{m} \frac{(z \cdot d)}{m}, \] where: - \( (aM) \) is the arithmetic mean, - \( D_m \) is the dose at which all animals react, - \( z \) is half the sum of the number of animals reacting at two consecutive doses, - \( d \) is the difference between the numerical values of two consecutive doses, - \( m \) is the number of animals in each group. An example is provided to illustrate the application of this formula. It is noted that the calculation of the mean error can only be performed using the method proposed by Trevan and Wiechowski, where the dosages tested in the series experiment correspond to the upper class limits of the corresponding frequency polygon.This article by G. Kärber discusses a method for collectively treating pharmacological series experiments, which has been applied at the institute for the computational recording of experimental data. The method is based on the collective measure theory, which has been extensively discussed by Trevan, Wiechowski, Behrens, and others. The key considerations in selecting a suitable computational procedure were: 1. The method should yield useful results even in cases of strong scatter in the series experiment. 2. The method should be applicable equally well to arithmetic and geometric progression of dosages. The formula used for calculations is: \[ (aM) = D_m - \sum_{m} \frac{(z \cdot d)}{m}, \] where: - \( (aM) \) is the arithmetic mean, - \( D_m \) is the dose at which all animals react, - \( z \) is half the sum of the number of animals reacting at two consecutive doses, - \( d \) is the difference between the numerical values of two consecutive doses, - \( m \) is the number of animals in each group. An example is provided to illustrate the application of this formula. It is noted that the calculation of the mean error can only be performed using the method proposed by Trevan and Wiechowski, where the dosages tested in the series experiment correspond to the upper class limits of the corresponding frequency polygon.