[fostermom]

Just managed to delete my post so I'll try again.
Without seeing the behavior, I can't tell for sure whether this is a play behavior..what I can tell you is your description sounds exactly like what my alpha male does. He's not interested in balls, or tug of war..but he LOVES to have me run around the yard, he chases, positions himself in front of me, eye-balls me and starts barking and either bounces up and down in place or makes mock "lunges" at me, making growly noises as he "lunges"..he NEVER makes contact and has figured out the clearances to a tee as he "misses" by fractions of an inch. He LOVES this..BUT will stop the instant I tell him to. (He also LOVES to be chased!!!)
He also likes to race down the steps ahead of the other dogs and grab at their necks as they go by (with zero bite pressure...again, just a mock grab)...the low ranking dog is a bit intimidated by this but the others just blow past him and ignore the behavior.
I'll leave it to others to try to interpret the behavior...but if I had to guess based on how Reno plays, I'd guess she's trying to enagage you in play. As to grabbing the other dog's neck...I do think with Reno there's a mix of play and asserting his alpha-niss in this behavior...I don't worry about either behavior as, again, he stops the moment I tell him to. He's also the self-appointed mother hen to the other dogs and cats, and an exceedingly "kind" dog so I don't view any of this as aggression.
If she isn't listening to you and escalating the behavior, I'd absolutely up the obedience so that she does comply when told...also maybe (as to jumping at you) I'd try ignoring the behavior...just like when a pup jumps on you...fold your arms, look up at the ceiling (maybe slightly turn your back) and IGNORE her...if she escalates the behavior too much (which she probably will to engage you...called an extinguishing bursty) leave the room or walk away...when it's no longer fun, she should stop. I'm sure others will have alternate suggestions to try also. I just wanted to give you some reassurance that this very well may be a play behavior. Best of luck.