Lorraine was in a hurry when she computed a confidence interval for m. Because was not known, she used a Student's t distribution. However,

Lorraine was in a hurry when she computed a confidence interval for m. Because σ was not known, she used a Student's t distribution. However, she accidentally used degrees of freedom n instead of n - 1. Was her confidence interval longer or shorter than one found using the correct degrees of freedom n - 1? Explain.