A STOCHASTIC-MODEL FOR THE PRESENCE ABSENCE OF READINGS IN NIORSTIGNINGAR SAGA

We consider the problem of reconstructing a stemma for the five extant manuscripts of the Nidrstigningar Saga. The method proposed uses a si mple stochastic model to check the plausibility of different suggested trees. The model is based on presence/absence recordings for readings in the documents. It is shown that the model can reproduce the numeri cal variation of the recordings to within reasonable accuracy. The mod el shows how the particular tree-structure is reflected in the frequen cy distribution of the 'profiles'. It also gives estimates for the rat e of loss of readings. Furthermore it is suggested how to infer the ex istence of lost documents from the estimated loss probabilities and ho w to estimate the size of lost texts. We also briefly discuss how diff erent assumptions on the rate of 'creation' (the amount of readings ad ded by a particular scribe) will force the investigator to accept diff erent stemmas.