Above we see yesterday's market (SPY) plotted against five minute closing values for the NYSE TICK. Recall that we visited the $TICK measure in the first lesson post that dealt with changes of market regime over a period of days. Now we are examining the change of market character that occurred intraday in Friday's market. Note that the scale for the $TICK values is in standard deviation units, so that we can see how stocks are trading relative to a recent lookback period.