Julie Hogan: Okay hands on activity.
Julie Hogan: So we're back in the let's just.
Julie Hogan: let's just find the schedule we're here now, this will be our last.
Julie Hogan: synchronous session together today and then there's three boxes below this.
Julie Hogan: That are for that or for offline work before we can meet again tomorrow sooner this afternoon or tomorrow morning, depending on your time zone.
Julie Hogan: The The challenge for this lesson and some some reading ahead for the blue colored lessons are coming tomorrow.
Julie Hogan: So we've got a couple things to play with right now.
Julie Hogan: So similar similar to what we did last time this is a little bit of a choose your exercise.
Julie Hogan: We would like you to try to do exercise one everyone, but then there are two exercises related to the be tagging so option A and option B, and you can feel free to choose whichever one works for interesting to you.
Julie Hogan: So, so this is a great time for any questions from the previous session great time to try out some of these some of these things in the code, since we talked about them more conceptually just before.
Julie Hogan: And and let's see how it goes i'll kind of poke around on a couple of them myself and then we'll go over the solutions here at the very end.
Julie Hogan: Hello Julie, can you hear me yes sorry my headphones were not working for some time, so I could not hear what you were saying, can you please repeat.
Julie Hogan: yeah sure so so right now what we're working on is the hands on exercises for the advanced object lesson.
Julie Hogan: So we're in if you're on on this page with the schedule we're in here.
Julie Hogan: And we'd like everyone to try to do exercise one, and then you can choose option A or option B.
Julie Hogan: For exercise to.
Julie Hogan: Now I didn't grab the new on correction tools so i'm going to start there and run not or which several of you did lower ninos.
Julie Hogan: Alright, everybody about 20 minutes left in this session so take at least seven eight more and then we'll go through.
We go through some of the solutions.
Julie Hogan: Certainly if you're having any trouble actually running the tools, please let us know or, if you have questions about the material.
Julie Hogan: Okay, hopefully, you guys had some success or running running these making a couple of edits.
Julie Hogan: Counting see things looking at some things let's start with exercise one.
Julie Hogan: So results of the new on corrections.
Julie Hogan: check that the corrections when apply but plotting we can basically plot corrected versus on corrected this is just in the money Carla because we don't have time to run the data file, so we don't have a full comparison here, but we can see what the correction is doing.
Julie Hogan: Just by plotting the two different masses.
Julie Hogan: So if you happen to have been watching my screen, as I was doing this.
Julie Hogan: slimming the X axis here is actually really helpful for finding the Z because we had a bunch of events that ended up down at zero, and I think there was even one event that ended up with a very, very large number, where we just We certainly didn't have a Z like dime you on mass.
Julie Hogan: for whatever reason, but when we use the route little tools here which actually I have a reasonable example of in the in the window right here whenever i'm drawing a certain branch I can apply some cut by giving in a different argument work my picture.
Julie Hogan: We can see the zippy quite nicely here in the black line is the this raw value.
Julie Hogan: And the red is what happens after we apply these corrections, so we can see that that definitely some of the the mass values have shifted.
Julie Hogan: If I look right here in the peak we're a little bit narrower right here in the peak region, although of course there's some spreading off to the sides because i'm i'm still just cutting on the same exact events events with a wrong mass between 84 and 98, so this is a very subtle collection.
Julie Hogan: home, you can kind of see what I was talking about that this is this is something that's of interest to the precision measures of things related to.
Julie Hogan: cool let's see if I got the same graph is, and you know.
Julie Hogan: looks really similar mm hmm yep awesome.
Julie Hogan: great and so here are some of those plotting commands that you can reference for how to how to apply cuts and how to draw things on top of each other in the same panel, which is a useful feature.
Julie Hogan: And here, actually, and you know, has provided us with the same plot for the actual data, so this is interesting, in contrast to the Monte Carlo where we're seeing most in kind of a.
Julie Hogan: shifting of the let's say the width as opposed to where the peak lies in data, you can see that what we're doing is we're shifting a Z mass that's a little bit too low.
Julie Hogan: In its peak position we're shifting it a little bit higher that's a really great comparison, so if you take the time to run the data file, hopefully, you will see the same thing.
Julie Hogan: Okay.
Julie Hogan: Be tagging had a couple of challenges here as well, so the first to add some alternate taggers So if you if you look back over the video you'll see me running through this I was just taking.
Julie Hogan: This list that prints itself out, oh no it's I guess it's not influencing my other screen.
Julie Hogan: There we go this list that prints itself out and I chose to add in the JET probability and the high purity track counting.
Julie Hogan: And we need to do that in a couple of places, so this is an overview if you've never done it before if it's new for you, how do you add go through and add a branch, we always have to declare the variable.
Julie Hogan: declare the branch and then somehow access the information and this solution is really missing one tiny elements that i'll show you in the file.
Julie Hogan: i'm just going to search the phrase jet the tag and let's walk through everywhere, it appears.
Julie Hogan: Declaration.
Julie Hogan: branch.
Julie Hogan: And then, for every event we declare out these factors, because the vector here is not saying here's the vector of all jets for all events it's the vector objects in this event.
Julie Hogan: So that's if you ever observed that your file sizes blowing up on you one thing to check is to see if you have neglected declare some vector and you'll be end up storing many, many copies of the same thing.
Julie Hogan: OK, and then here we go, we can grab these grab these different strings from the be discriminated function.
Julie Hogan: So here in the solution, I plotted out what the track counting variable looks like it's completely different.
Julie Hogan: than the completely different than the csv discriminate or which was a value from 01 this one's actually has a physics, meaning it's related to the impact parameters and I wanted to point out this reference so we've we've referenced here.
Julie Hogan: and actual what we call physics analysis summary which is on algorithms for the JET identification and so you can find you can find all of the information about the various tigers references.
Julie Hogan: What I was looking at here on my screen is the other one the probability.
Julie Hogan: And I drawn i've drawn it in two halves kind of so what i've drawn here is the JET probability tags for jets that past the csv algorithm edits tightest working point so this one that's in the solid histogram should be real be tags according to the the other algorithm.
Julie Hogan: And then the points here the ones that are in points in error bars, these are, this is the JET probability discriminate when the JET be tag.
Julie Hogan: Which is the csv algorithm was extremely small so it's very light pork like so actually you can see, this is a good discriminate or as well we're light corks pile up near zero in this jet probability discriminate her and the Court jets have a have a higher value numerical data.
Julie Hogan: And then the very last exercise was to count oh I you know I still have some fun, though, the very last exercise was to count the number of jets prevent that or be tagged according to this medium working point of the CSP algorithm.
Julie Hogan: So I did that I think we can find that in here as well.
Julie Hogan: Okay store branch called jet and CSP me, so I followed my own instructions, so that I know what's a search.
Julie Hogan: And you can see, all the same pieces declaration.
Julie Hogan: branch.
Julie Hogan: initializing it in this case to zero, as opposed to clearing a vector and in all these cases.
Julie Hogan: i'm following the template of what I see above and below me and i'm you know if if declaring route branches is new, for you, I was like i'm looking at the templates of all these other things, to give me a pointer as to how I should do that.
Julie Hogan: Okay, and then we actually need to count, so if the combine secondary vertex rejects jet tags discriminate or is greater than 0.679 which I got from the lesson page the medium working point I will increment this counter.
Okay.
Julie Hogan: So let's take a look at that that should live here in my tree somewhere, here it is way up at the top.
Julie Hogan: So in this in this top work sample I tend to have 567 jets got quite a few jets.
Julie Hogan: And then, if I look at how many are be tagged.
Julie Hogan: peek at one lots of them also at two so that makes perfect sense we expect there to be to bottom forks in our top court parents.
Julie Hogan: We know we don't have a sweet, you know, this is a 65 or 70% efficiency to identify them, so a peek at one with a large component to make sense, I can turn this off of log scale as well.
Julie Hogan: and see what it looks like in linear scale yeah.
Julie Hogan: Very few with three even fewer would for a couple of zero So you can see, actually, you know i'm I have a significant amount of my top forks that just don't their their bottom corks don't look like on works, according to the algorithm and that's too bad, but it happens.
Julie Hogan: Okay, so what I really want to look at our what happens when I apply the uncertainty so let's do this let's apply, excuse me, the uncertainty is the wrong word, the scale factor.
Julie Hogan: This branch is called jet and CSP.
Julie Hogan: let's put on the be tag wait.
Julie Hogan: Oh, are these spelled wrong in the solutions.
Julie Hogan: You bet they are.
Julie Hogan: You bet they are there's an underscore.
Julie Hogan: Okay, a question for Option a sorry if I missed that should we clear the vectors that we're filling.
Julie Hogan: In the JET loop each event, yes, so you should you do not need to clear them in the Jet Blue you just it's sufficient to clear them at the beginning of the analyze function, because the analyze function is called for everyone.
Julie Hogan: So that is what you can do.
Julie Hogan: Okay, so I apologize to anyone who's copying and pasting because of the wrong spelling of these weights.
Julie Hogan: So let's do this, let me go ahead and draw this one with.
Julie Hogan: dots i'm going to draw dots.
Julie Hogan: But I don't really want aero bars right now so i'm going to say P history and that we're getting the dots without airburst.
Julie Hogan: So what we're going to see the solid line is the raw number of.
Julie Hogan: The tech jets and now we're going to see what happens when we apply the scale factor.
Julie Hogan: Oh, we get a super tiny dot okay not helpful let's make the finger.
Julie Hogan: By using some of our gui tools.
Julie Hogan: i'm going to make it bigger and i'm going to turn it back.
Julie Hogan: Bigger there we go.
Julie Hogan: Okay, so what is applying the scale factor do applying the scale factor has shifted the mean of this distribution down.
Julie Hogan: That makes sense, we saw in the lesson that Monte Carlo over predicts the number of B corp jets, and so we expect applying the scale factor to reduce that number that's what we're seeing.
Julie Hogan: What about uncertainties, what about uncertainties, we have other wait function so means my editor.
Julie Hogan: We have wait wait up and wait down.
Julie Hogan: So let's draw weight up and we're gonna have to watch roots teeny tiny dot.
Julie Hogan: Here we go.
Julie Hogan: Okay now somewhere is my editor.
Julie Hogan: There it is okay let's make it blue.
Julie Hogan: squares and they are.
Julie Hogan: Okay, do we shift the uncertainty up, you can see, we actually get a different a different answer, and we would see the same thing if we shift the uncertainty down so i'll just go to the solution where i've already got this plot.
Julie Hogan: With a nice legend here's how I made that legend I right clicked somewhere in the space and I chose build legend.
Julie Hogan: And I accepted their default options and then you can like drag it around.
Julie Hogan: Okay, so you can see we've got a shifting lower of the of the Nina the distribution and then we've got an uncertainty i'm in this case it's I think I did a quick calculator it's about 6%.
Julie Hogan: Uncertainty on this distribution do this source so that's a look at some of the other some of the techniques related to these new on corrections and this be tagging and a little bit of practice at navigating a poet, and these boot files.
Julie Hogan: So we will come, we will come back tomorrow.
Julie Hogan: we'll go over the solutions to the challenge, just like we did at the beginning of this morning and then we'll have the analysis will us and the beginning of the cloud computing lesson we will see you guys tomorrow.
Julie Hogan: Thank you bye.
Dillon Fitzgerald: bye everyone.