It measures the ammount of buying going into up shares and the amount of selling going into down shares. It tends to confirm a markets move or intraday trend. There is little leading value to this indicator. In generally, you do not want to get bearish while the Trin is still dropping though. This has been the case in the summertime where any extremes int he ticks tend to occur in the first and last hour.
Institutional activity is notably absent during the middle of the day.
Normally, the ticks will swing back an forth in an 800 tick range. Main comment we could make about the ticks is that they have been positive all day. But that is because breadth has been positive all day. The two period ROC has rallied up for two days. The market is making a two day corrective bounce.