In Cabecar, Guaymi and Tunebo, the ergative marking element may also be interpreted, from a synchronic point of view, as an agent disambiguator
Already the statements on the utility of disambiguation for short queries have been supported through experimentation by Sanderson  who showed a small improvement in effectiveness for retrievals based on single-word queries when documents and queries were represented by word senses, identified by an automatic disambiguator. Similarly, results of experiments investigating manual disambiguation of short documents (image captions) by Smeaton and Quigley  has also provided evidence showing effectiveness improving for this type of retrieval.
The analysis of sense frequency distributions presented in this article provides an explanation for the results of Schutze and Pedersen  whose use of a disambiguator on large queries and documents resulted in a 7-14% improvement in retrieval effectiveness, the first published results showing an automatic disambiguator working successfully with an IR system.
To understand the reasons for their results, which apparently contradict those presented here, it is necessary to first explain how Schutze and Pedersen's disambiguator worked.
(2) Ng and Lee stated that the error rate of their disambiguator was 30%.
Gale, Church, and Yarowksy introduced and tested a disambiguator using pseudowords in a 1992 paper [Gale et al.
Such systems are known as word sense disambiguators. Early disambiguators were based on hand-built rule sets and only worked over a small number of words and senses [Small and Rieger 1982; Weiss 1973].
The number of mistakes made by disambiguators appears to vary depending on the subtlety of word sense to be discriminated between.
This means, despite the fact that the majority of the instances show at least one formal disambiguator (86.4%; 367 out of 425), that here, too, the reader can select between the SVO and OVS interpretation on the basis of semantic factors, since predications where one of the arguments refers to a person and another to an abstract or concrete nonhuman entity are rarely reversible in the sense discussed above.
Most languages possess more or less systematic formal disambiguators that enable the listener/reader to attach adequate syntactic functions to NPs.
It is commonly assumed in such studies that morphological and syntactic phenomena are used as disambiguators that are expected to trigger revision of the analysis pursued so far (see, e.g., Mitchell 1994).
In Swedish, this holds for all the word order phenomena presented as disambiguators so far.
When there are no formal disambiguators in the sentence, the thematic roles can only be assigned by utilizing word meanings and real world knowledge.
Summing up, then, we contend that the morphological and syntactic factors listed in this section have an impact on the process of decoding and that calling them disambiguators is therefore justified.
More specifically, the following topics will be discussed: (a) do formal disambiguators affect the occurrence of OVS word order (Section 2)?