Other issues to consider…
What do YOU feel most comfortable with in defending your house/family? What gun are you more proficient using? Do you practice with a gun AND a light (for nighttime scenarios)? What gun might work best in your house? Does your house have lots of small rooms? Does it have rather large areas? Are the bedrooms close together or scattered around the house? Are there childrens’ toys frequently laying all over the floor? What are the points of entry for a BG? Etc…
I have practiced going through my house at night, in the dark with both a shotgun and a pistol (seperately) using a flashlight and then with a weapon mounted light. I did this to see what worked better for the layout and physical postition of my architecture, furniture, and where points of entry (for the BD) would be. I noticed things such as MY safety and efficiency at moving around corners with each weapon, “slicing the pie” down hallways and from hallways, how to enter a room or even whether I should enter a room. This simple drill allows the user to see how to really handle armed movement in his home and where movement may be better handled by responding police and not at all by the homeowner, depending on the nature of the threat. Sometimes taking a defensive position or leaving the house ASAP is the best choice.
Things I learned about moving through my house in the dark trying to cover every realistic threat angle made me realize that that is a big job. Add to this trying to locate and protect family adds to the complexity of the problem.
Even doing this drill alone at home in the dark creates its own stress. The first couple times I did this I was amazed at how my heart rate was faster, my breathing quicker, and my senses seemed to be much more in tune to my environment. Imagine the stress of thinking there is a BG in your house!
A personal example of this: 22 years ago I was home alone at night. Old rental house, not the best neighborhood, 3 am. I knew my roommate was out of town and would NOT be returning. Noises from outside my bedroom awoke me. I woke with a start and lay there awhile trying to discern exactly what I was hearing. It certainly sounded like there was a someone or someones in my basement. I grabbed my 9 mm and carefully and quietly made my way out of my bedroom and through the upstairs level. I had to do this to get to the phone on the other side of the house. I slowly cleared each room on my way across this ground level of the house to reach the phone. I was happy there was nobody upstairs with me but the noises continued from the basement. One glance at the stairs leading to the basement door convinced me this was a 9-1-1 police job. I was NOT going downstairs! My heart rate was through the roof by this time. I called the police, they showed up in about 2 minutes (small town), I explained what I thought was happening and they took the lead. 2 big cops headed down stairs while 2 more searched the perimeter. No BGs found. What had happend was a small window had fallen in (or been pushed in?) the screen was torn (the window was large enough for a man to fit through btw) and two possums has taken to rough housing in my 70 year old unfinished basement. They were making quite a scene apparently when the cops entered the basement.
To conclude- I was happy there was no intruder, no threat, and the cops did what they did with professionalism and coutesy to me. However, I could not sleep the rest of the night as I could not calm down. Just the idea that there was someone in my house in the middle of the night was damn nerve racking.
I know people who HAVE had people break in to there home at night while they were there. Even years later it bothers them greatly. Have they changed their outlook on being a victim of a crime? Yes. Have they planned and prepared a little to combat this if it happens again? You bet your a$$ they have.
You said you want to use data to reach conclusions. I recommend you take all you learn from your “theoretical studies” and apply that to your own personal situation to gain the data you need for the job only you will be best at dealing with if and when the time comes. See for yourself what works best in a situation that will be unique to your home. This may help you choose a weapon and it will definately help you apply your ability to you need.
The shotgun can be and is a fantastic home defense choice. It could certainly not be the best choice, depending on too many variables to cover here. Only you will be able to determine what works best for your home environment.
My 2 cents is that a short barreled 12 ga pump loaded with 00 low recoil buckshot is perfect for my application. Perhaps it will be for you as well. Practice with the weapon, weapon and light, and shoot lots of rounds of your chosen load to see how it works out of your gun.
Best wishes!