I think basically there is not much difference between the structure AA and A-A. Examples can be found in 想想 想一想；试试，试一试。 让我想想。让我想一想（想一下） ：Lets see/ let me think. 让我试试（试一试） let me give it a try

I agree with Daisy! To give you examples of how different they are, here are two identical sentences except one uses 看看 and the other uses 看一看： 我们打开看看 Let's try to open it 我们打开看一看 Let's open it and take a look (inside) Hope this was helpful!

they are different. 试试，try on 看一看，have a look

本題之解答與以下提問相同 http://www.italki.com/question/227599 漢語的重疊型式