text_combined: eott options tracy attached spreadsheet model contains black scholes american option valuation models generally accepted methods valuation options equity european option prices assume option holder exercise options maturity american style options exercised time life assumed examples underlying equity units market value 13 00 options struck level volatility input main assumption eott trading recently volatility ranging 30 40 although looking back range much wider run model must linked options library sure lan connected coordinate zimin lu x 36388 help loading option library add module ena lan located research exotica xll exotica xll loaded excel using tools add ins browse reach add location stinson x 34748 p mail hard copy plot showing recent eott volatility well would like us help running specific examples please let vince zimin know