Accrual valuation and mark to market adjustment
  This paper provides intuition on the relationship of accrual and mark-to-market valuation for cash and forward interest rate trades. Discounted cashflow valuation is compared to spread-based valuation for forward trades, which explains the trader's view on valuation. This is followed by Taylor series approximation for cash trades, uncovering simple intuition behind accrual valuation and mark-to-market adjustment. It is followed by the PNL example modelled in R. Within the Taylor approximation framework, theta and delta are explained. The concept of deferral is explained taking Forward Rate Agreement (FRA) as an example. 
Alexey Bakshaev
q-fin.PR