I've always been told that if you kill a spider another one will take its place..
I can see the logic behind this... Spiders are there for a reason.. If a spider sets up home in your house it means there is a source of food for it, so if you kill the spider, what ever it was eating, will have a sudden population burst.. since there is nothing there to eat them.. then there will be enough food for more spiders.. so technically,. i guess, if you kill a spider, it could cause more to come.
Never heard that before but if they come in your house, it would be better to catch them and put them outside. They are beneficial to the environment in that they eat mosquitoes and other bugs. So only kill them if absolutely necessary.
I'd think that it would repel other spiders, but I've noticed that when I kill one (rarely) I do tend to see more afterward...I'd bet that's just because there's been a nearby hatching.
So...I can't say yay or nay, just give you my observations and opinion, which parse out to "maybe."