Judged: two independent readers; copy check clear.
Spearman–Brown prophecy formula
Spearman–Brown prophecy formula The Spearman–Brown prophecy formula is a psychometric method used to predict how reliability will change when repeated measurements are combined, such as averaging across more observation days.
The Spearman–Brown prophecy formula is a psychometric method used to predict how reliability will change when repeated measurements are combined, such as averaging across more observation days. In assessment research, it is often used to estimate how many observations are needed to reach a target level of reliability, though the packet notes this can overestimate longer-term reliability when based only on short-term data.