CHAPTER 10

Gaining power –the dreaded ‘too few participants’

10.1 IF THERE IS SOMETHING THERE, MAKE SURE YOU FIND IT

Statistical power is about whether an experiment or study is likely to reveal an effect if it is present. Without a sufficiently ‘powerful’ study, you risk being in the middle ground of ‘not proven,’ not being able to make a strong statement either for or against whatever effect, system, or theory you are testing.

You’ve recruited your participants and run your experiments or posted an online survey and gathered your responses; you put the data into SPSS and … “not significant” (Fig. 10.1). Six months’ work wasted and your plans for your funded project or Ph.D. shot to ruins.

So, how do you avoid the dread “n.s.”?

Part of the job ...

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