Some end of day spikes are attributable to short covering since some folks don't want to hold on to their positions overnight or over the weekend. If you're familiar enough with a stock (i.e. those you watch all day) you may be able to catch the bounce. Typically the stock gets puked out in the morning, beaten all day and just stays at the same price with high volume but there's a bunch of buyers in there too - you can see this with FTR this past Friday, which went from $3.92 to $4.00 by end of day (after hours). +$0.08 or +2%, you pick. I'm not a shorter, but if a stock isn't down for any fundamental reason that I haven't been able to discern (i'm research intensive), it's usually a shorter. In those times I've caught it right, I've been lucky - not smart!
There were some great answers provided to my question a couple weeks ago on why it takes so long to determine the SPX closing price, www.elitetrader.com/et/threads/why-so-long-to-calculate-the-s-p-500-closing.303088/#post-4335280 I definitely learned a couple things from our resident experts who've worked that on the inside.
If you got a big order to fill during the day and you didnt get a good average price, you can try and run the market at the end of the day to make your fill look good to the client compared to the closing price at least.
Very old school. Of course you're using the clients money to make his earlier bad fills look good. Sort of a double insult. Doubt many are fooled by this ancient method in 2016.