1 The hypothalamus, pituitary gland, and the gonads (ovaries, testicles) operate in a feedback loop, producing and maintaining the levels of sex hormones (androgens and estrogens) that are mainly responsible for the primary and secondary changes of puberty.
Calculation: Here is the formula for FIP: FIP = ((13*HR)+(3*(BB+HBP))-(2*K))/IP + constant. The constant is solely to bring FIP onto an ERA scale and is generally around 3.10. You can find historical FIP constant values here, or you can derive the constant yourself.
Today's statistic: FIP. What it stands for: F ielding I ndependent P itching, devised by Tom Tango, based on research by Voros McCracken. How they calculate FIP: Tango's simplest version is expressed by the following equation.