We recently received the results from a survey attempting to measure parent satisfaction with their child's school. I did not design the survey but have been asked to report on the findings. About 80% of our students are classified as economically disadvantaged and about 35% have a primary language other than English spoken at home. Our communications department wanted to provide parents and guardians with the option to take the survey online or use a paper scan sheet because many of our families simply can't afford a computer.
I've attached the results with the items in misfit order as well as some very puzzling results with regard to dimensionality. At the end of the attachment are the results from the t-test. With extreme scores included, there is clearly a difference in responses between those families using online versus paper. But once the extreme scores are removed, there does not seem to be a significant difference.
Wanting to investigate further, I calibrated the items using all students (566), then only those that took it online (193) then those that handed in paper scan sheets (373). The dimensionality tests for each run are very different, though all three seem to indicate a 2nd dimension of some kind. But each reports this as something different.
For example, when all parents were used or only those using paper scans, the 2nd dimension seems to have something to do with "This School" items. However, when only the online parent data were used, the 2nd dimension seems to be centered on staff.
I would very interested in your thoughts about this.