Directional Bias For The Day: The futures are directionless and awaiting Chair Yellen’s speech at Jackson Hole at 10:00 AM Swing low of 2168.50 is critical for S&P 500 On Thursday at 4:00 PM, S&P future (Sept contract) closed at 2171.75 and the index closed at 2172.47 – a spread of about 0.75 points Key Levels: Critical…