Wednesday, January 06, 2016

Alder Tree Seeds: Inferential Validation - Ha Ha, Kind Of

Alder Seeds, Floating in Water
So yesterday I blogged about stratifying seeds for the hedgerow, and noted that the alder seeds whose cones I'd picked up from the pavement were floating when I put them in water, which anyone who forages seeds will know is a sure-fire indication of the seeds' non-viability. But I did theorise that, as alder generally grows by water, it would make evolutionary sense that its seeds could be dispersed by water, and floating away would be a good thing.

And that appears to be the case, according to treesforlife.org, (scroll down to "Water").  Because I'm desperately trying to get my head back into my Doctorate reading, I'm going to make some analogies here to Kane's (2013) ideas about inferential validity.

I inferred yesterday, that because alder grows by water, it could be argued that their seeds should float, and therefore flotation was not necessarily proof that they weren't viable, (which would be the case with, say, rose seeds). The information from treesforlife.org tends to validate that inference. but it's not conclusive. If, however, the seeds germinate, then we can be sure the inference has been validated. I'm kind of stretching a social science point about validation into the world of hard science, (botany, about which I know very little), but it works metaphorically.

Thus clumsily bridging from  the allotment to the virtual library and the cerebral business of test validation, forth I go...


Kane, M. T. (2013). Validating the Interpretations and Uses of Test Scores. Journal of Educational Measurement50(1), 1–73. http://doi.org/10.1111/jedm.12001