What is the figure used regarding positive vs. negative interactions between parents and children?

I was asked about the issue of positive versus negative interactions between parents and children.  The statistic most commonly used is 8/10 interactions are negative and involve a cost to the child.  The result of a high number of negative interactions is children's selective listening.  If the child thinks that what he/she will hear is negative then they select to not pay attention.  The fix for this is to increase positive interactions so that they child will think that the massage being directed their way is more likely to be positive and so they will want to pay attention.