Electricity markets in the United States are evolving. Accurate wind power forecasts are beneficial for wind plant operators, utility operators, and utility customers. An accurate forecast makes it possible for grid operators to schedule the economically efficient generation to meet the demand...

Exact lower bound on the correlation function and susceptibility are obtained in terms of the quantity r∗=r0+(12u/(2π)d)∫ ddl〈ϕlϕ−l〉, where 〈ϕlϕ−l〉 are the exact averages. Further lower bounds are obtained on r∗, relating it to an exactly soluble model.