Dozens of parents and children showed up for a hearing on the District’s paid family leave bill in October. (Jabin Botsford/The Washington Post)

Regarding the Jan. 18 editorial “Not your federal petri dish”:

Accurately estimating the costs of implementing any plan to provide paid leave to workers for illness and family care requires a nuanced understanding of demographics and worker behavior. The Institute for Women’s Policy Research has studied paid leave since 1990 and spent years developing an economic model to incorporate these nuances. Our analysis found the D.C. Council’s paid-leave proposal affordable.

The IWPR model accounts for the District’s demographic variables, such as how many women in the workforce are of childbearing age, how old and at risk for long-term illness (either themselves or a loved one) workers are and whether employees are highly paid and employers provide good benefits. It then predicts who will take paid leave and for how long based on the behavior of employees and employers in states that have implemented similar programs.

Several researchers’ back-of-the-envelope estimates show that the council’s proposal is too costly. The methodology behind these higher estimates — prepared by people with expertise in taxes and regional business, not paid leave — may be easier to understand, but that does not make them more accurate. We invite people to learn about our evidence-based analysis before making up their minds.

Heidi Hartmann, Washington

The writer is president and chief executive of the Institute for Women’s Policy Research.