systems. On the positive side, most systems have 

 well-documented file structures. 



Most of the systems are able to generate some sum- 

 mary reports based on the data base (feature 12). A 

 majority could also produce a report on incremental 

 changes over time. But few had a direct linkage to a 

 statistical software package. For those that did not 

 have this direct link, many exported the desired data 

 to an outside file in a readable format, and then had 

 their statistical software program utilize this gener- 

 ated data file. Though a direct link would be desirable, 

 this alternative method at least provides a convenient 

 way for the data to be used by external statistical 

 software. 



Additional Features 



The last question on the first questionnaire asked 

 the person to list any additional capabilities their sys- 

 tem needed to improve performance for their applica- 

 tions. Half of those surveyed with existing systems 

 indicated that some additional features would be use- 

 ful. Of the additional features that were needed, many 

 of them were related to the DBMS features previously 

 described. Most of the needs listed fell into the gen- 

 eral categories of ease of use and analysis. Other re- 

 sponses were related to error-checking, storage, and 

 retrieval of data. 



The large number of responses related to ease of 

 use suggests that some of the systems are highly de- 

 pendent on experienced users, potentially limiting the 

 use of these valuable data by those with lesser skills. 

 The number of responses seems to suggest a desire to 

 develop systems that are accessible to a range of users, 

 from novice to highly advanced. The responses related 

 to ease of use include the addition of user-friendly 

 menus for operation, full-screen and interactive edit- 

 ing, easier methods for inputting field data, better data 

 output capabilities, direct access or links to statistical, 

 graphics, and GIS software, the system programmed 

 in the up-to-date version of the base language instead 

 of out-dated earlier versions, and, finally, better PC- 

 based systems instead of systems dependent on mini- 

 or mainframe computers. 



A need for an improved ability to analyze the data 

 was emphasized by some of the respondents. Within 

 the DBMS, analysis needs included listing and plotting 

 growth computations on the computer screen and pro- 

 grams for comparing and analyzing data from several 

 measurements together. There was also a need by 

 several users to interface the data base with analysis 

 programs, written in FORTRAN and other languages, 

 that resided outside the DBMS. 



Several respondents felt that they needed better 

 error-checking capabilities or error-checking that 

 could be used in an interactive mode. Two of the re- 

 sponses indicated a desire for better storage of data, 

 namely, data stored without repetition or storage of 

 more than one measurement period's data in the same 

 files. In regard to retrieval of data, respondents wished 

 for improved search techniques as well as faster pro- 

 cessing of search requests. 



CONCLUSIONS 



To take full advantage of the investments made in 

 remeasured plots, the data must be carefully managed. 

 The evaluation of existing systems, as well as the de- 

 scription of important features of a DBMS for remeas- 

 ured plots, provide guidance for those charged with 

 the management of their valuable resource of remeas- 

 ured plot data. This information can be used to help 

 prioritize improvements needed in existing systems, 

 and also as a framework for the development of new 

 systems. 



REFERENCES 



Byrne, J. C; Stage, A. R. 1988. A data structure for 

 describing sampling designs to aid in compilation 

 of stand attributes. Gen. Tech. Rep. INT-247. Ogden, 

 UT: U.S. Department of Agriculture, Forest Service, 

 Intermountain Research Station. 20 p. 



Sweet, M. D.; Byrne, J. C. 1990. A standardized data 

 structure for describing and exchanging data from 

 remeasured growth and yield plots. Gen. Tech. Rep. 

 INT-271. Ogden, UT: U.S. Department of Agricul- 

 ture, Forest Service, Intermountain Research Sta- 

 tion. 43 p. 



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