Depends on lighting conditions but generally, yes. Which is least partially why I ended with the question that I did.

You'll discover very quickly that using motion cues to trigger anything other than a light outside is either going to generate a bazillion false alarms or basically be so insensitive as to miss everything. In my opinion, your best bet is to setup two zones: the exterior zone and the interior zone. For the exterior zone, several fake cameras (really just camera-shaped pieces of plastic with a blinking light) plus a few otherwise indistinguishable real ones plus DVR can be had for pretty cheap (Costco, for instance, has kits as low as $250ish). You can use either the built-in motion detection or cue from an external unit (haven't done this myself but I expect it to be pretty straightforward based on how I've triggered similar systems in the past). Key piece: make sure that the storage ends up being put somewhere reasonably secure, away from the DVR and things that look like they're worth stealing.

For the interior zone, I'd use same trick(s) except this time you want to trigger off window opening / door opening sensors as well as motion sensors. The hard part will be to make sure you match up to consistently. I'd want a hysteresis threshold (after x seconds of consistent motion, send a snapshot, after an additional y seconds turn on the sirens).

All in all, it's pretty straight-forward but it's likely to be time consuming, which leads me to: are you sure that what you need is a security system to re-establish your sense of security?

SSH != crypto algorithm.

I got bored this afternoon and did the proof a few different ways. Unfortunately, the details won't fit in this comment box.

they are surprisingly inexpensive ($500 plus some labor w/ analog video downlink). they are also likely to have been repaired quite frequently (that is if you're lucky and didn't leave a pile of kindle your last encounter with gravity).

on an unrelated note, it's fun to watch confirmation bias in the wild.

you missed my point.

yes, the market will ultimately dictate the value of a skill set; however, any organization that sends the message that experience and a demonstrated track record when it comes to building and improving core products is at least 23% less valuable than the flavor of the week, something is broken. alternately, you can see their decision as a wager that risking the morale of their organization so that some kid fresh out of college who claims to know X would, somehow, pay off. neither seems particularly wise to me.

i would walk. there is something clearly fundamentally broken with that particular organization and its leadership.

a couple thoughts:

1) approximate randomized algorithms are your friend, especially when we talk about things like (RAN|MAP|MLE|M)SAC in model fitting. for some classes of problems, random approximate algorithms are the *only* attack that we have that are feasible in terms of time/space complexity.

2) your analysis fails to account for the hidden leading constant (otherwise there's no reason to consider quicksort when you have heapsort) and what happens when N gets to be large enough. the fact is that for big enough N or big enough S, the lower order algorithms will start to become dramatically faster, even if repeated applications are necessary to cross-validate results.

3) unless you're using arbitrary precision math, all of these algorithms are approximate anyway and great care must be taken to understand how these systems can be (pre)conditioned to minimize the compounded effects of fixed precision arightmetic.

touche.

how so?

let me summarize: the same math that drives google's search (spectral graph theory) has been shown to be really useful in solving a very common class of linear equations if you're willing to roll the dice (randomize algorithm).

not really.

the method applies to the _general_ (i.e. dense) case of diagonally dominant (i.e. |A_i,i| > |A_i,j| for all i,j) symmetric systems that show up all the time (grammian matrices, for example), not just the sparse case.

give me $30k in consulting fees and i'll tell you who to hire.