Linnea N. Meyer ’07, one of this fall’s Phi Beta Kappa inductees, offered words of hope yesterday for the first-years longing to be accepted into the prestigious national honor society.

“My very first, and worst, grade at Harvard was a C-minus in a rhetoric course freshman year,” said Meyer, a Social Studies concentrator in Winthrop House. “It was the lowest grade I’d ever gotten in my whole life, but it really motivated me.”

Meyer was among the 48 seniors notified of their election into the Harvard chapter of Phi Beta Kappa, the Alpha Iota of Massachusetts, last week.

Nine of the honored students were economics concentrators—more than twice the number of inductees from any other concentration. And in a departure from most of the chapter’s 225-year, male-dominated history, the group selected this fall is balanced evenly between men and women.

The Registrar’s Office culls the names of students with the highest GPA in each of three fields—humanities, natural sciences, and social sciences. Alpha Iota then picks exactly half of those students, based on two faculty recommendations and the rigor of their courses, and with an eye toward academic diversity.

“If 25 percent of the class are natural science concentrators, then 25 percent of the 48 students will be from natural science fields,” said James F. Coakley ’68, the secretary of Alpha Iota. “In the old days, we used to just have one meeting and pick the 48 students, but it was very hard to compare physicists and musicians. Now we have three different meetings.”

Coakley called the even number of men and women this fall a coincidence. According to Coakley, gender is not a consideration during the process, and historically there have been more men elected than women.

“It’s not purposefully gender balanced,” Coakley said.

The Harvard society, which inducted its first members in 1781, is the country’s oldest continually running chapter, according to its Web site.

Phi Beta Kappa elects students three times a year: 24 students in the spring of their junior year, 48 students in the fall of their senior year, and about 90 or 100 students at the end of senior year.

The total number of students invited to join Phi Beta Kappa is approximately 10 percent of the graduating class.

Anushka M. Sunder ’07, an economics concentrator in Cabot House, said her academic environment helped her excel.

“Having an interest in the courses I was taking helped me to stay motivated, and it’s really nice to have teachers who acknowledge your work and take a more personal interest in you—that has definitely helped me to stay engaged,” Sunder said.