TABLE 5. Estimated transition probabilities of farms from 1978 to 1982. States S S S S S S 8 S S S S 0 1 2 3 4 5 6 7 8 9 10 S 1 0 0 0 0 0 0 0 0 0 0 0 S .176 .824 0 0 0 0 0 0 0 0 0 1 S .224 0 .776 0 0 0 0 0 0 0 0 2 S .352 0 0 .593 .055 0 0 0 0 0 0 3 S 0 0 0 0 .912 .088 0 0 0 0 0 4 S 0 0 0 0 0 .790 .210 0 0 0 0 5 8 0 0 0 0 0 0 1 0 0 0 0 6 8 .250 0 0 0 0 0 0 .625 .125 0 0 7 S .333 0 0 0 0 0 0 0 .556 .111 0 8 S 0 0 0 0 0 0 0 0 0 1 0 9 S .400 0 0 0 0 0 0 0 0 0 .600 10 step. The transition matrix, in addition to the initial starting state, completely defines the Markov process; i.e., with the foregoing information, it is possible to determine the outcome of the process at the n'h step. Estimation of the Transition Matrix The efficient estimation of transition probabilities often presents a major technical problem because such estimates de- pend on the quality of the data available. However, three alter- native approaches are possible: statistical estimation from micro- unit data, from aggregate data, and from conceptual considera- tions (Collins et al., 1974). This study, following Krenz (1964), adopts a conceptual approach to the estimation of transition pro- babilities. The Bureau of the Census does not provide data on in- dividual farm units in the quinquennial censuses, and only enumerates farms in one of the several categories given above. By making use of detailed information on the life of farms in the Virgin Islands, patterns of behavior are assumed and rules subse- quently adopted in order to determine the transition pro- babilities. In this regard, the following assumptions are made. First, it is presumed that most farm operators in the Virgin Islands would want to expand their acreage if it is possible to do so. Second, it is more likely that medium to average size farms will expand because of financial resources available, and because of economies of scale, than it is that small farm units will increase their acreage. Third, any increase in farm size is likely to proceed gradually by the acquisition of adjacent property. Such incremen- tal aggregation is likely to be a function of the availability of agriculturally zoned land, and of reasonable financial ar- rangements for purchasing land. Fourth, individual farms are not likely to decrease their unit size voluntarily, particularly because of the problems of economies of scale. Rather, it is more probable that a farm will go out of business than exist as a reduced entity. It is on the basis of these assumptions that the following two rules are adopted in determining the transition of farms from one state to another. An increase in the number of farms in any state S;, from one time period to the next, comes from the next smaller state, Si-. A decrease in the number of farms in any state indicates a move- ment to So, a state of demise. The application of these rules of behavior to the data at hand produces the transition matrix that is utilized below. One advantage of the transition matrix is that it provides useful insights into the movements of farms that are not readily available from other types of projection models. 26 TABLE 6. The fundamental matrix of mean five-year periods The Application of Absorbing Chains In the movement of farms between states discussed above, it was indicated that states So is that state in which all farms that go out of business eventually end up, and the assumption was that they remain there. Such a state in a Markov chain is defined as an absorbing state if it is impossible to leave it. A chain is therefore absorbing if it has at least one absorbing state and from every state it is possible to go to an absorbing state (Kemeny et al., 1962). With one absorbing state in this study, that of going out of business, the model employed here is an absorbing Markov chain. The application of the theory of absorbing Markov chains thus permits one to generate very useful answers to a number of questions (Kemeny et al., 1962; Bartholomew, 1982). First, what percentage of farms that are in a given state S, (or size category) are likely to be amalgamated with farms in a larger size category Sj after five years? This question can be answered by examining the coefficients of the transition matrix. Second, for any farm of a particular size, how long is it likely to stay within its size classification before it amalgamates with another? Such a question can be answered from the elements of a fundamental matrix. Thus, the coefficients of this matrix give the mean number of years (of five-year duration) in each transient state for each possible nonabsorbing starting state. Third, on average, how long does it take before a farm in a given size category is absorbed or goes out of business? The sum of all the entries in a row of the fundamental matrix will give the total length of (five-year) time periods that a farm is likely to sur- vive before going out of business. Fourth, what, in absolute numbers, is the distribution of farms, according to size categories, likely to be in five years, in ten years, or in n years? Or, how many farms in total will there be in five, ten, or n years? Of the two alternative methods for projecting these numbers, use is made of that which multiplies the distribution of farms in the base year, 1978, by the canonical form of the transition matrix P to generate the projected distribution for one period; then the result is postmultiplied by P for the needed number of periods (Krenz 1964). For complete details on the estimation of the fun- damental matrix and related statistics, see Kemeny and Snell (1976, pp. 43-50). Empirical Results The frequencies used to estimate the transition matrix were derived from the census data of 1978 and 1982, and by the ap- plication of the rules stated previously. The particular quality of the Virgin Islands census data dictated that only the data for 1978 and 1982 could be utilized in the generation of the transition PROCEEDINGS of the CARIBBEAN FOOD CROPS SOCIETY-VOL. XX