Most new isssues do not go up or at the least stay up, only the ones that get press, the public seldom hears about the ones that don't move (especially on the down side).
As usual ASHOK wrote an epistle that does not answer the question submitted (just a lot of words with some information, some of it not correct.)
Investors want a bargain, too. Thats why, if the mass stock world feels like the ipo is too high, they will bring down the price with their buying. Heck, even facebook soon went down after their ipo, from $38 to $22. Facebook is at around $62 now so it all worked out but its tough to tell. Just dont panic and sell immediately after a stock goes down. They often climb back up after some time.
There are few clues:
Look SEC filings and find if there are good institutional investors on it.
Look pre market activity, if there volume before the market opens, sometimes, IPO after delay 1 or 2 hours after market opens.
Look for the spread bid/ask and time/sales volume.
But the best way to go IPO is to wait after few week the stock will set a higher high and bounce lower, set that higher high on your broker alert, and when price bounce back and break that higher high, your broker will sent you the alert and buy buy buy!
You analyse them just like you would a stock that is already listed.
You don't and sometimes they don't.
it's a gamble but they often do go up
