1. A method for triggering notifications to a population, comprising: receiving, via a network, responses to a first stimulus from a portion of the population, wherein said receiving is performed for a first period of time; tabulating, via a computer system, the responses to the first stimulus received during the first time period from the portion of the population; determining, via the computer system, that the tabulated responses to the first stimulus exceed a first threshold during the first time period; triggering, via the computer system, broadcast of the first stimulus to the population in response to said determining that the tabulated responses exceed the first threshold during the first time period, wherein said triggering operates to notify the population of the first stimulus; receiving, via the network, responses to a second stimulus from the portion of the population, wherein said receiving is performed for a second period of time; tabulating, via the computer system, the responses to the second stimulus during the second time period from the portion of the population; determining, via the computer system, that the tabulated responses to the second stimulus exceed the first threshold or exceed a second threshold during the second time period, wherein the second threshold is based on elapsed time since broadcast; determining, via the computer system, that a time period between broadcast of the stimulus and broadcast of the second stimulus exceeds a specified duration of time; and triggering, via the computer system, broadcast of the second stimulus to the population in response to said determining that the tabulated responses to the second stimulus exceed the first threshold or the second threshold and said determining that the time period between broadcast of the stimulus and broadcast of the second stimulus exceeds a specified duration of time, wherein said triggering operates to notify the population of the second stimulus.