What does ‘statistically significant’ mean? It’s just a way of expressing the likelihood that the result you got was attributable merely to chance. Sometimes you might throw ‘heads’ five times in a row, with a completely normal coin, especially if you kept tossing it for long enough. Imagine a jar of 980 blue marbles, and twenty red ones, all mixed up: every now and then—albeit rarely—picking blindfolded, you might pull out three red ones in a row, just by chance. The standard cut-off point for statistical significance is a p-value of 0.05, which is just another way of saying, ‘If I did this
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