In multivariate testing on Mail.ru advertising platforms, what statistical method confirms that observed performance differences are not due to random chance?

In multivariate testing on Mail.ru advertising platforms, statistical significance testing confirms that observed performance differences are not due to random chance. Statistical significance testing involves using statistical methods, such as the Chi-square test or t-tests, to calculate a p-value. The p-value represents the probability of observing the obtained results (or more extreme results) if there is truly no difference between the tested variations. A small p-value (typically less than 0.05) indicates that the observed differences are statistically significant and unlikely to have occurred by random chance alone. In the context of multivariate testing, this means that the variations that performed better are genuinely superior to the others, rather than the observed differences being simply due to random fluctuations in the data. Without statistical significance testing, it's impossible to confidently determine whether the observed performance differences are meaningful or simply the result of chance, which can lead to incorrect optimization decisions. Essentially, statistical testing helps you identify the signals from the noise.