to answer the OP what I would do is use a point light hidden inside the lamp. Set the point light to inverse square falloff so that it behaves like a real world light source. In the example here I am using TrekkieGirl's render room and one of the stock Poser lamp models. I set the lamp shade material to either SSS or translucent so it would transfer light though it. Make sure you have at least 6 diffuse bounces to get the light right otherwise it will be too dark. in the second example I'm using 1 area light facing straight down and situated right under the ceiling in the middle of the room. Area lights always work on inverse square.

W10, Ryzen 5 1600x, 16Gb,RTX2060Super+GTX980, PP11, 11.3.740