The dissemination of divination in roman republican times

practices above the upper line. We can compare this with the 13 practices we have investigated
(cf. fig.9.3).
Dissemination
3,5
3
2,5
2
1,5
1
0,5
0
0 1 2 3 4 5
Credibility value
Figure 9.3. Survival of divination practices 184
We can see that there are no examples in the upper right corner, as we expected from equation
2. We can also see that the different practices are located in the high probability zone across the
diagram (the bright rim): Some rely on high credibility value, while others rely on high
dissemination. We do have three practices that do not follow this picture in the lower left corner,
but they are exactly the two that died out, as was expected from equation 4. The actual names of
the practices can be seen on figure 9.4. where those that do not survive are marked with a cross.
A strong word of caution on the interpretation of these figures is however necessary here. First,
the values in the graph are the product of interpretation, not accurate measurement. Second, the
interpretation is very insecure and conjectural since the sources very rarely directly address
dissemination or credibility value. Third, there are so few data points (13) that the introduction
of one new one could opset the picture. We cannot therefore be very certain about the results.
While the graph does not proof, it is still in accordance with, what we would expect based on the
theoretical model.
184 Table 9.1 was converted into numerical values to make the diagram. Credibility value: Very high=4, High=3
Medium=2, Low=1; Dissemination: Wide=3, Medium=2, Small=1
188