A nonprofit organization is determining which existing donors will donate again for a current campaign. The organization decides to look at its donor database for all donors who have donated two or more × over the past five years. Which measures should be used to determine the probability of receiving a donation from an existing donor over time?

The F-statistic is primarily used in the context of regression analysis to compare models and assess the overall significance of predictors. It does not provide a direct measure for predicting donor behavior or likelihood of future donations, making it unsuitable for evaluating individual donor contributions.

The median is a measure of central tendency that indicates the middle value of a dataset. While it can provide insights into average donation amounts, it does not offer a comprehensive view of donor likelihood for future contributions, as it does not account for variability in donor behavior or frequency of donations.

R-squared is a statistical measure that represents the proportion of variance for a dependent variable that's explained by independent variables in a regression model. While useful for understanding model fit, it does not directly assess individual donor behavior or predict future donations, thereby lacking practical application in this scenario.