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Quantitative Analysis of Responses

450 completed questionnaires were received from 450 sites. 81 respondents identified themselves as NIH grantees. Figure 1 (p. 14) displays graphically the mean response for each item accompanied by bars showing 1S.D. and the effective sample size for each item. The left panel pertains to the existing program and the right panel relates to planned features not yet implemented.

 User Profile (items 1-7, 13, 14)

An overwhelming majority of VMD users are affiliated with academic institutions (84%) and use VMD for research (78%). 19% of the respondents reported to be funded by NIH. Almost all VMD users run the program on Linux and IRIX. About 60% of the respondents would also like to be able to use VMD on Windows 9x and Windows NT. Most of our users first heard of VMD via the web (53%) or from friends (26.5%), and they clearly prefer to be informed of VMD news by Email (57.9%) or web announcements (38.8%). The respondents reported an average of 2.3 users per site.

 Evaluation of Present Program (items 8a-8d, 12)

On a scale from 1 (= strongly disagree) to 5 (= strongly agree), the mean satisfaction score of VMD was 3.84 with an S.D. of .79. The overall satisfaction is highly correlated with the mean response to all evaluative items (r=0.55, p<.05). The joint distribution of these two variables is shown in Figure 2 (p. 15).

The respondents reported that they use VMD because it:

Having a free graphics program is considered an obvious advantage, alongside strong technical and GUI qualities. The low variance produced by the respondents indicates a high level of agreement on all four items.

 Expected Usefulness of Future Features and of Interfaces to Other Tools

The expected usefulness of 7 future features of VMD was rated on a scale from 1 (=unimportant) to 5 (=very important).

The lowest rated features were:

The top rated features were:

The respondents felt that they would benefit most from using VMD with four of the tools listed: Amber (118), Charmm (111), XPLOR (94) and Insight (85).

 The Quality of VMD Support

The quality of VMD support was assessed on a scale from 1 (= strongly disagree) to 5 (= strongly agree).

The users agreed that:

The clarity of the documentation and the instructiveness of the web pages were ranked significantly higher than the other support aspects measured. Here, again, the low variance produced by the respondents indicates a high level of agreement on all items.

 Comparative Analysis

We performed several comparative analyses between various groups. In most cases we did not uncover any significant differences. There are only two noticeable exceptions. As shown in Figure 3 (p. 16) NIH-funded users ranked their overall satisfaction, as well as satisfaction with developers' responsiveness and the extent to which VMD meets their needs, significantly higher than non-NIH funded users. Figure 4 (p. 17) indicates that with a single exception academic users report a higher level of satisfaction with VMD, and on eight specific items this difference is statistically significant.


next up previous contents
Next: Qualitative Analysis Up: Results Previous: Results

John Stone
Mon May 24 11:10:57 CDT 1999