Which S/N value indicates a statistically significant difference in mean word recognition scores across four word lists when tested at various levels?

Which S/N value indicates a statistically significant difference in mean word recognition scores across four word lists when tested at various levels?

• A. 10
• B. 0
• C. -15
• D. -20

Answer: (B)

The key idea is understanding how signal-to-noise ratio relates to detecting a real difference across multiple lists. Statistical significance here means that the observed differences in mean word recognition across the four word lists are large enough to stand out from the random variability you’d expect when testing multiple lists at different levels. A signal-to-noise ratio of zero means the signal (the true differences between lists) and the noise (measurement variability) are at the same level. In this context, that balance marks the point where the method is most sensitive to whether there is a real difference across lists. So, a S/N value of zero is the threshold at which a statistically significant difference across the four lists is indicated, given typical testing conditions. Values higher than zero imply a stronger signal relative to noise and can still show significance if a real effect exists, while negative values suggest noise dominates and significance is less likely.

The key idea is understanding how signal-to-noise ratio relates to detecting a real difference across multiple lists. Statistical significance here means that the observed differences in mean word recognition across the four word lists are large enough to stand out from the random variability you’d expect when testing multiple lists at different levels.

A signal-to-noise ratio of zero means the signal (the true differences between lists) and the noise (measurement variability) are at the same level. In this context, that balance marks the point where the method is most sensitive to whether there is a real difference across lists. So, a S/N value of zero is the threshold at which a statistically significant difference across the four lists is indicated, given typical testing conditions. Values higher than zero imply a stronger signal relative to noise and can still show significance if a real effect exists, while negative values suggest noise dominates and significance is less likely.