esc_2x2 giving different results than Wilson's

[djmeter]

I ran the following code and got a different result than with the web-based 'Practical Meta-Analysis Effect Size Calculator' from David B. Wilson (http://www.campbellcollaboration.org/escalc/html/EffectSizeCalculator-Home.php)

esc_2x2( grp1yes = 205, grp1no = 98,
grp2yes = 512, grp2no = 178,
es.type = c("r") )

Could you please let me know why the formula is different? Thank you! Diana