Call buttons are installed at traffic lights with a dedicated pedestrian signal, and are used to bring up the pedestrian "walk" indication in locations where they function correctly. In the majority of locations where call buttons are installed, pushing the button does not light up the pedestrian walk sign immediately. One Portland State University researcher notes of call buttons in the US, "Most buttons don’t provide any feedback to the pedestrian that the traffic signal has received the input. It may appear at many locations that nothing happens." However, there are some locations where call buttons do provide confirmation feedback. At such locations, pedestrians are more likely to wait for the "walk" indications.