I'm a senior research statistician developer
here in the Design of Experiments and Reliability group
at JMP Statistical Discovery.
Its quite a mouthful.
A s you probably guess from the title of my talk,
I'm going to be talking about autonomous vehicles,
and specifically how we can probably assess the reliability
of autonomous vehicles
using some of the reliability platforms like JMP,
so that may be one day we'll be like this fine gentleman here
relaxing in our autonomous vehicles as they take us wherever we want to go
without being scared that we won't end up there.
L et's get into that.
O f course, autonomous vehicles are fast becoming a reality.
We have a lot of companies now involved in extensive testing of these vehicles.
Now, of course, some of that testing early on
is basic testing of the software, testing in simulated environments,
but ultimately, in order to have a very reliable vehicle,
you need to test it out on the roads,
and so to help out with that, a couple of years back,
the California Department of Motor Vehicles
put together a testing program that would allow these companies
to opt in and test their vehicles on their roads.
As part of that arrangement, though,
every year these companies have to provide a detailed report
on any disengagement, and heaven forbid, crashes
involving their autonomous vehicles to the DMV.
Now, because the DMV is a federal institution,
these reports are actually publicly available upon request.
In fact, I'll pull up a link here real quick to the California DMV website
where you would be able to go to.
In this case, you could access reports from the last two years.
If you wanted more, you just send an email to this link
there pretty quick on getting back to you.
Now, already a lot of people are using this data in academic research.
As a quick example, I'll click on this link here
to a paper on a project that I was personally involved in
with my former advisor and one of his new PhD students,
in this case, analyzing it using what's called, recurrent events data.
I'll talk a little bit about that more later.
But again, there's already research looking at how can we use this data
to assess the reliability of autonomous vehicles,
maybe use it to introduce new methods and so forth.
I t's already been starting to be widely used.
Now for this particular talk, I'll be looking at disengagement reports,
using that as a way to measure reliability
because of course, we can't access the actual software,
that's all proprietary for the company.
But through the use of these disengagement events,
we can infer the reliability of the vehicles for a particular company.
A gain, I'll be showing off,
this is a JMP statistical discovery conference,
so I'll be showing off some tools in JMP that allow us to get that information.
Wi th that, let's quickly talk about what data are we looking at?
W hat are in these reports?
F irst, these are annual reports,
and I'm going to be focusing on a single company,
those coming from Waymo,
which is formerly this Google self-driving car project.
T hese are reports submitted by Waymo to the California DMV.
Now, I've been talking about a disengagement event.
What do I mean by that?
Well, there's two types of testing.
The first involves there being a driver in the seat,
the vehicle actually can't operate without a driver in the seat.
But at some point, they can turn on autonomous mode,
and if anything happens where the driver has to take over,
that was not planned as part of the testing,
that's a disengagement event.
The other type of testing, of course, is a completely driverless vehicle.
We're not going to focus on those.
We're just going to focus on the driver necessary systems.
Now, these annual reports go all the way back to about 2015,
even containing information back to 2014,
which is about when this whole California DMV program started.
Waymo was actually one of the first companies to get involved in this.
T hese reports contain, first of all, they contain data
typically from December of the previous year,
to November of the current year of the report,
the exception being the 2015,
which actually goes back a bit further into 2014.
F or example, the 2016 report would have data from December of 2015,
all the way up to November of 2016.
T here's two general types of data present.
The first is going to tell you all about the disengagement event.
What was the cause? Where did it happen?
S ometimes it might give you the day and the VIN of the vehicle
involved in the incident.
The other type of report is,
how many miles were driven in autonomous mode
for a vehicle, for a particular month.
Now, you may have noticed that I said, in the disengagement event report,
sometimes we know the date and the event.
Yes, that's right.
It's not very consistent across the entire time.
In fact, that information actually wasn't available until 2018.
Prior to that, we only know what the event was and how many happened within a month.
Starting in 2018, they started providing that information,
most likely because the DMV encouraged them to do so.
W hat it means then is that
you actually have two levels of resolution with our data.
T he first is at a month level,
and for that we can go all the way back to when testing began.
I'm going to be looking at that type of data
using our reliability growth platform.
T he other type of data is actually daily and at the VIN level,
so individual vehicle level.
I'll be using the recurrent events platform to analyze that.
Before I continue further, let me show you where those are.
You'll find them under the Analyze Menu, go down to Reliability and Survival.
You'll notice a ton of platforms here.
The one I'll be highlighting are Recurrence Analysis.
Th is is, we got individuals, in this case, vehicles,
that can experience a recurring event over time,
in this case, a disengagement event,
so we'll be using that for the VIN level, and then the reliability growth
I'll be using to analyze the monthly aggregate data.
The same idea,
although reliability growth is more for if I have a big system
that could encounter m ultiple events,
sometimes they have to be repaired as part of the event,
so they're experiencing it over time.
It might go through different phases in,
so the underlying process or software might be evolving over time.
That's something that the reliability growth platform is intended to handle.
Now this could also handle the VIN information as well.
It's fine with that.
I'm just picking these two because I want to show off the breadth
of the stuff that we have here at JMP.
While I'm doing that,
I also want to show you a bit of how we use some JMP tools to compile the data.
Obviously, there's a lot of reports,
so how do we compile all that together into a single report?
I'll touch briefly on some of the tools that we used in JMP to help with that.
L et's dive right into that.
F irst I'll talk about reading in some of the earlier reports.
Y ou've already noticed there's a bit of inconsistency in what's reported.
There's also a bit of inconsistency in the format of the reporting,
so some of the very early reports were in the forms of PDF.
Let me show you an example using the 2017 report.
W e have a nice report here from Waymo.
It's very well formatted.
In fact, this is probably one of the better, nicer reports
that we've seen amongst the companies that were participating at this time.
A bunch of tables in here,
The ones we really want are the ones here at the end in the appendices.
This is an events report.
Notice days a bit of a misnomer.
It's actually the month where it happened,
some information about the operation, what caused it.
We definitely want this information.
This is a table that we want.
We also want a table here at the end
which shows the autonomous miles for each event, in this case the last four.
Don't even get the complete Vin for each vehicle for each month.
Now, of course it's in the PDF,
so we really don't want to have to go in and manually type these in.
It would be nice if JMP had a way to read in tables from a PDF.
Well, you're in luck because I can go here and do open.
There's my pdf I've marked it to, Select all files, not just JMP files.
There's my report, I'm going to click Open
and we have our fancy PDF reader.
Now, what it's gone through is it's trying to identify everything that's a table
in that report and it's done a pretty good job.
Scroll through here.
You can see captured most of those tables.
In fact, probably too many tables don't need all of these.
You can scroll through them individually using this dropdown menu
and you can see it's labeled by page and the table number on that page.
I don't need all of these tables as I mentioned before,
I just want the ones that are in the appendices.
That's easy.
I'll go to the Red Triangle menu that suddenly appeared on the page
and say, Just ignore all the tables on this page.
I'll scroll down and do the same thing for this page.
Okay, now I've got the tables I'm interested in.
We still need a bit of tweaking to do because as you'll see,
they're essentially each table on each page is its own entity.
So these are actually all the same table.
How do I tell JMP to do that?
Well, now I can go to the Red Triangle menu on the table.
I'm going to scroll down here to number of rows to use this header
and tell it to use none.
Now what this means is if there's a table prior to it
that's telling JMP that, hey,
that's actually part of the previous table.
That's why there's no header on this.
I'm going to click zero.
You'll notice that table, there's one less.
You've also noticed it's added two columns in this case.
What page is that table occur and what table on that page.
If you wanted that information, JMP automatically provides it.
In this case, I don't really need it,
but I can delete it later after I'm done reading these then.
We also notice we missed a bit of that table
probably because the formatting change
notice it was able to pretty easily find what the roads were for this table,
but for this one, not so much.
Mainly because of this guy.
Some we just didn't put it just right, so it didn't fit the pattern.
That's okay, I'm going to click, I'm going to drag around
and that tells JMP, "Hey, there's you a new table",
and I can go in right now thinks it's a zone table.
I can just tell it no, it's part of the previous one.
There we are.
I'm going to scroll through and yeah, it missed some of this information.
But again, notice it's trying to maintain that formatting,
but because of the way it was input, it missed that last row.
That's okay I can input that information later. It's not a big deal.
If we go to this next page in this case JMPs done the opposite.
It's actually concatenated these two together, which makes sense.
It sees these are pretty close together.
Maybe they are the same table.
Unfortunately, they are not.
As you can see, they're two distinct tables here,
whereas here they're concatenated together.
I need to tell JMP.
No, that's actually a different table.
That's pretty easy.
Just say how many rows.
No, there's actually is a header row,
and that tells JMP, that's a different table.
Now it's created a different table.
I would have to repeat that for a lot of these.
Unfortunately, the way they've input this,
I'm going to have to do a bit of work later on
to get them in the right format.
But that's okay.
There are other tools and JMP to do that.
For right now for the sake of time I'm not going to go into that.
I just want to show you how we could read it in from a PDF.
Now, thankfully, starting in about 2018,
they started using Excel for their reports.
It was a lot easier to just copy and paste directly into JMP.
Now that we've got the raw data tables in,
I'm not done yet because I would like to reformat some of these data tables
to get them into a nice common formatting
that can then use to concatenate them all together into a single table.
Now I'll show you how I did that,
and it's actually quite a lot of things that I want to do.
Here's an example of the Waymo 2022 report.
We in this case,
we have the date of the incident, the VIN number of the vehicle involved.
This is just extra information that I actually don't want to keep.
It's just saying, can I drive by itself?
Is it completely driverless? No.
Yes, sir. Of course there's a driver present.
Who initiated it. I'm not going to use that information.
I'm going to keep the location and the description.
This is essentially the cause.
I will probably rename some of those columns.
I also need to summarize over this table,
because from this I'd like to create an aggregate events
so I can use it with the monthly aggregate data.
I would need to aggregate summarize over the VIN numbers over the dates by month.
Do all that, so if you bear with me,
I've a lot of about five minutes or so to do that.
I know it's a bit dangerous to kind of do that live, but just bear with me.
First thing I need to do is I need to open this guy
and then I need to click this button.
Okay. Give me.
Let me take a little break here. That was a lot.
Thank you for bearing with me on that.
As you can see, thanks to something new called the JMP workflow,
I was able to accomplish all of that in a fraction of a second.
Well, maybe a little over a second, but still a lot faster.
I've got a data table here aggregated by month.
I got the location, the cores, how many events happened in that?
I can relabel some of that and I've got my individual data table
that has the date, the VIN and the actual individual events.
I've got that set up.
Now I can save those in different locations to be concatenated later.
What is this new workflow?
Well, let me open up a new one for you just so you can see it if can get there.
There we go.
This is what you would start off with.
What you do is you click this red record button and on an individual data table you
would then it would then record the actions you're taking on that data table.
This is very useful if you have an this like I have here, I have a lot of reports.
I'm going to be doing the same thing for each report.
Then having to instead repeat all those actions for each of those tables,
I just record it for one table and then save it as a workflow.
Then when I ran it, what it would do is it would open up
a window saying, "Hey, couldn't find that original data table.
Can you show me what the new one is?"
Select it and it runs it.
Now, in this case,
it didn't do it here because I already had it primed for this data table.
But typically if the data table has changed in the name,
so long as it keeps the same formatting,
that's the only thing you have to worry about.
If a column did change a name, that's okay.
JMP also knows to ask,
"Hey, couldn't find that column. Can you give me a replacement?"
This is very helpful.
Let's say you have a daily report that you have to collect data on
so you would get a data table of that report.
Maybe there's a couple cleaning things you need to do on that data table.
Save a workflow, open that data table,
click Run, select the right data table and you're done.
This is a great time saver.
This really helped save us a lot of time
when we were compiling these data together.
That was something that was just recently introduced in JMP 17.
I'm sure you're going to love that.
Let me exit out of all of these. I've already got those tables done,
and want to make sure we're going to go on to the analysis
because want to make sure we have time to do that.
Let's start with the monthly aggregate level.
Here I've compiled it across all the time periods
up until the most recent, that being 2022.
Let's quickly walk through what I've got here.
I've got date in this case, it's the month.
How many vehicles are actively being tested in that period?
How many total autonomous miles were driven in that month?
This is how many different event types happened.
This is the total number of disengagement events that occurred.
Let's do a quick visual look at this.
JMP is all about graphs and visual exploration.
Let's look at that.
Here I've got plotted the cumulative number of events over time
and the individual events and we notice is an interesting little pattern here.
There seem to be there's clear spikes and then drops and it seems to happen
about 4 or 5 times where we see this spikes.
You can also see that with the cumulative data.
Ideally what you would like with this type of data,
there'd be a bit of an increase at the beginning
and then it's going to flatten out.
Ideally, it becomes completely flat.
If you do that, you have achieved the perfect autonomous vehicle.
You have no more disengagement incidents to worry about.
But of course that's never going to happen.
You just want it to be as flat as possible.
What we're seeing, of course, is a bit of a rise or a burn in period,
if you will, and then it's starting to flat out.
But we have that repeated a couple of times most significantly here.
That's a pretty big jump there.
Of course, you can see that correlating here.
We've got our burn in period.
Then as we drop in the number of incidents,
our curve up top is going to flatten out.
This is going to be the key piece of information we are going to be looking at
in our reliability platforms.
We've got that information there.
Now I'll go ahead and quickly address one question that might come up.
Maybe you might think, well,
maybe the more you drive it, the more incidents you might have.
Maybe we should try and account for that and I have.
Here's another graph where I've looked at the correlation between, in this case,
the log of the mileage and the log of the total disengagement events.
There is a bit of a trend.
It's a very small one.
In fact, the R² is not good at all.
There's a lot of spread in the data.
Here's actually the prediction equation with its individual prediction boundaries,
there's a lot going on.
There's plenty of room for a flat line there.
This is just saying that there
might be something like that happening, but it's clearly not the driving force.
Yes, if you drive it a little bit more, you might experience a few more incidents
that make sense.
But it's clearly not a big driving force.
Something else is clearly going on.
Hopefully that helps address a side question that might come up.
Well, let's get into the actual reliability analysis.
I'm going to run this script here,
and this is going to run that reliability growth platform.
Don't worry.
After I've run it, I'm going to click here under the Red Triangle redo relaunch.
This brings up the initial launch.
This is what the initial launch window looks like.
You have four different ways of entering the data.
The first is a time to event.
If you had recorded here's how many days or months up until an event happened,
you would use this one.
Then you could of course, maybe multiple happened at that time.
You could put that there.
We have the dates, which is what I'll be using because we instead of an actual
timed event we just had saying that in this month this many events happen.
We have a timestamp and an event count for that.
You also have it if you have individual information,
maybe we're doing concurrent testing or testing in parallel.
You can do that information here.
Notice there's a spot for the system I D.
If I were looking at the individual event information,
this is where I would go.
But for right now, we're going to stick with the dates.
I'll revisit the phase stuff in a moment.
You'll notice it's plotted that cumulative curve, which we saw earlier.
There it is right there.
Now the metric of interest here is what's called mean time between failures.
It's clearly oriented towards reliability data
where we're looking at failures.
Think of this as what's the average month
between incidents, disengagement incidents.
There's a bit of a non-parametric
measure here that's just sort of a moving window, looking at it over time.
But you can get a sense of how good we get, maybe how poor we get.
I'm actually going to fit a model.
The model I'll be fitting is here under fit model.
This was a bit of a mouthful.
It's a piecewise viable in change point detection.
Let me break that down for you.
The typical model used in modeling this type of account type data
is what's called a Poisson process.
What that's essentially says is that the rate at which incidents occur
in this case rate per month is constant over time.
That would be the equivalent of a straight line here
from a mathematical perspective, that's a nice model.
It's very easy to analyze ,
from a practical perspective that is a horrible model
because we never get to improve.
Our rate of incident is always the same.
We don't want a constant rate.
We want the rate to go to zero, preferably.
That's what I mean by that flattening of the curve.
What we want is what's called a Non-homogeneous Poisson process,
fancy term meaning the rate changes over time.
The weibel part says how exactly does it change over time?
It consists of two parts.
There's an initial rate lambda Think of that as like a constant out front
and multiply that by time raised to some power beta.
That value beta is going to tell you how the rate changes.
If beta is greater than one, my rate is increasing over time.
That's bad, we don't want that.
That rate were zero.
We're at a Poisson process. It's constant, we also don't want that.
What we're looking for is a value of beta that's between 0 and 1 saying, you know,
okay, it'll increase a little bit, but then it's going to start to die off,
it's going to slow down getting us that leveling off that we want.
When we estimate these, we're looking at a value between 0 to 1.
We're also looking visually for that flattening off.
For the meantime, between failures, what we want is that to get very large,
ideally it'd be infinite, meaning it'll never happen,
but of course that can't happen.
We just want very large mean times between failures.
I'm going to fit that model here.
I'm going to use a change point
because that's saying that at some point
maybe that value of beta in my model is going to change significantly,
mainly because of this guy here.
I'm going to run that because it looks so different.
Yes, according to this,
there is a change point right there, a pretty significant one.
If you look graphically,
that's not a great fit, but it's not a really bad fit either.
But it is detecting that something significant happened in 2021.
If we go to this plot,
this is showing you how does that mean time between failure changed over time
and it's doing it for each in this case phase.
This is sort of the empirical phase based on this change point.
In the first phase, it says, well, we got to about as good as 0.15 months.
That's roughly five days between incidents, not too bad.
Roughly a week.
Again, this is across a fleet of vehicles.
For any individual vehicle, it could be longer or shorter.
But for the fleet,
essentially the software itself, about a week between disengagement incidents.
After 2021, it drops significantly to about 5%.
That's almost a day and a half.
That's quite a drop.
We can look at the parameter estimates. There's my data, that's just my initial.
Notice For beta one it's less than one, we're doing great.
For the second phase, not so much.
In fact we can see maybe we could do a little bit better.
Notice there were about four of those, so maybe I can invoke
some sort of empirical grouping on that,
which is what I've done in the other script.
It's going to run this.
All I did here. I'll do the redo, relaunch?
I just added a column called Empirical Phase
that's just got a bunch of letters in it
that just distinguish the phases from each other.
It's a categorical factor.
That's all it is, and that's what these vertical lines represent.
This is a combination of me repeatedly using the change point.
It only detects one change point.
You can do a trick where I can select some of the data, hide and exclude it,
and then do it again.
That's a way for it to drive detect different change points.
Some of this is also just me eyeballing it.
Full confession.
Now for this one, the model all fit is called a piecewise Weeble.
The same thing is what we did before.
But instead of it detecting the change point, it's saying,
I've already got those in for you.
Each time you see one of these changes,
these different phases, that value of beta is going to change.
It's going to connect them all together.
But that value of beta might change,
indicating a change in the process overall based on these phases.
This is a much better fit.
It's maybe it's a bit of a too much overfitting.
I will acknowledge that.
But if we look at this, what it's essentially saying is
for that first initial period of changes in the software,
were you about got almost as good as 0.4 months.
That's almost 12 days between incidents.
It's still saying that we got really good up until 2021 and then we've dropped.
Clearly something is going on in around 2021.
Something significant has changed
in the underlying software across the fleet of vehicles that's dropped.
That's increased its incidence rate.
There's those parameter estimates.
Again, notice I'm going to ignore that one.
That's a burning period.
A lot of these are less than one
until we get to the season D's, which are afterwards.
Clearly something's happening because it's larger than one.
We're already we've got a bit of a story.
Something clearly happened in 2021 to change the incident rate.
Maybe when we look at the individual data, we'll figure out what's going on.
Let me clear out all of this and let's move over to the individual vehicles.
Quick summary. We have our date.
The actual date of the incident,
the vehicle identification number, the VIN this VIN group, it's nothing fancy.
It's just the first four digits of the VIN.
You're going to see why I've created a group in a moment.
I've got the location, the cause.
I've reduced the text of the cause. It was very wordy.
I just reduced it to a basic description.
We'll cover that in just a moment.
The starting and ending month.
I've got this information basically telling me
how long was this vehicle under test?
This particular vehicle,
it was basically being tested in autonomous mode on and off
from December of 2017 to about November, maybe October of 2019.
We're going to need that information.
I'm going to first look at some basic some graphical summary.
First thing I'm going to do, I'm going to run this.
This is just going to summarize over the causes.
Let me look at the total number
of disengagement events for each vehicle each month.
Then I'm going to run this plot
and you're going to see it's going to look interesting,
like coral under the sea, waving about very pretty.
A lot of information going on.
But the basic thing I want to tell you is
the way to interpret this is like we did with the cumulative events graph.
That's what these are.
You want to see a bit of a burn in, but it ultimately flattening off.
Now I've got a colored by individual then, which is why you don't see the labels.
There'd be way too many.
I'm going to color by a different variable this time.
We're going to color by the VIN group.
Come here under color.
Again, that's just the first four digits of the VIN number,
which clued me in because let me throw in the legend so you can actually see it.
Show legend.
I'm done.
Notice there was a significant change in the VIN number
indicating maybe a significant change in the vehicle.
Notice when the change occurred right around 2021.
Very interesting.
You can also see a general trend in the behavior for these early vehicles.
Now, some of these probably actually started earlier than this.
There's a bit of censoring involved, but already they're pretty flat.
We've got a bit of burn in and then some flattening off.
That's great, that's what we want to see.
These guys, there's almost a straight line up.
We've got a lot of incidents happening in a very short period of time.
Now, later on here, later in 2022, there are starting to lean off a little bit.
We've got some that did start and they're starting to be pretty shallow curve.
That's good.
But clearly something's happened here.
This seems to indicate that a different vehicle
and perhaps a different type of software was introduced about 2021.
It's having some issues.
It's struggling a bit, or at least initially did.
About here it's performing about as well as we saw early on.
They've they've done better in fixing it.
They introduced something new and had a bunch of bugs.
That's what happens when you introduce new things.
Let me exit out of this.
Let's look at maybe something about a different type of cause.
Now, remember, in the previous video,
we didn't really look at the cause because it was aggregated across all the vehicles.
But let's look into that real quick.
Maybe there might be something going on there.
Before we actually get into the recurrence data.
Here I've just done a basic bar chart of the causes,
and a lot of them are things you might expect to be a cause.
An unwanted maneuver
equals doing something you don't want it to do, a perception discrepancy.
The vehicle didn't see something it should have
or thought it saw something that wasn't there.
Then there's, of course, software, a general catchall software discrepancy.
Something happened with the software.
There are some interesting causes.
For example, other people being jerks on the road.
A reckless road user car didn't know what to do.
Adverse weather, incorrect behavior prediction, hardware discrepancy.
These are the basic causes.
Now, I'm going to use a feature called a Graph Lit
to investigate things further.
I'm going to right click inside this bar.
I'm going to hover label, I'm going to click Bar.
What it's done is it's added a little bar chart Graph Lit.
When I leave my bars there with a hover, here's my little Graph Lit.
Now, by default, it's going to use the first categorical factor it sees,
which was the variant number.
I don't want that.
I actually want the date.
I'm going to open the control panel here.
I'm going to put the date here and replace it.
I'm going to right click in the date.
Because it's a date.
This was recently introduced.
Think it was either 16 or 17.
I can actually bend by a particular type of date,
in this case I want to bend by a month?
Perfect.
I also would like to color by the VIN group.
Just so that we get a clear comparison of the different types of groups.
Notice there's a bit of purple here.
That means there is some overlap, which makes sense.
There was a bit of overlap from end of 2020 to 2021 with a new groups,
but now we can clearly see,
compare visually the groups across the types of incidents just visually.
I'm going to come here, I'm going to go back down to save script to a clipboard.
I'm going to exit out of this
because right now, if I hover, it's no longer there,
but I can right click go to hover label and paste Graph Lit.
Now it's going to show me the graph for each of them.
In fact, I'm not going to click and zoom in
because we can see what's happening.
There's not too much there's this is the unwanted maneuver.
There might have been a bit more unwanted maneuvers,
but that's more of a general spike
in overall terms, not much difference, I would say,
for the perception discrepancy pretty much on par.
There's a bit more in general here, but I'd still say comparable.
Sort for discrepancy.
Whoa, let's look into that.
Okay, This is very interesting.
Apparently with the old group,
there was hardly any software discrepancies, maybe one.
Whereas with the new group, there's a lot.
Interesting.
There could be some explanations.
It could be that the way the category was defined maybe changed over time.
Maybe there were other things.
It was re categorized as other things for the old one
before they change the definition for this new group.
That's a very valid explanation.
It could also be taken at face value.
Maybe there were a lot of other different causes with the old one.
Maybe if we look, we're able to look back early on
at the individual vehicle information for the earlier data,
maybe we would have seen a spike in the software discrepancies.
Because this is later in that series testing,
maybe we did those out a little bit.
We're just seeing these early bugs happening with the new vehicles.
Let's actually now go into the recurrence event analysis now for current events.
That's just saying have an individual object that can
experience an event repeatedly, in this case a disengagement event.
Over time.
I'm going to run the script
and then do the redo relaunch so you can see what I did.
Do. I'm going to do relaunch by group.
In this case, here's what you would get if you opened it up.
In this case, you have an age or event timestamp.
When did it happen? Have a timestamp. The date.
What's the system? That's the VIN.
What's the cause?
Well, hey, great to have a column called cause
it's going to basically break it down by the different causes.
You can look at these different causes.
The timestamp. When did I start testing on this thing?
Basically, when does it undergo start?
When did I stop looking at it?
What's the timestamp?
I put the VIN group in by, I could have put it in grouping,
but there is a bit of an issue where if there's not a lot of data
in the causes for both of them,
it's not going to be able to compare them.
For right now, I'm just going to use a by group, a VIN by group.
We can still do a sort of visual comparison.
For the scaling you can select that
I've done today because that's the level of resolution we have.
It'll do it in a day just for interpretation, ease of that.
Okay, so we're looking at this first group.
This is the early group two for our group.
Notice it's broken it up by all the different causes
and they're pretty similar.
The hardware discrepancy seems like the biggest one,
if I'm reading that correctly. Yes, that's hardware.
Notice this is what's called a mean cost function.
It's similar in interpretation to that cumulative function.
You're looking for the same behavior,
a bit of a rise, but you ultimately want it to flatten out.
This is saying what's the average sort of incidence rate
for a single vehicle by this age?
It's a little bit harder to interpret than
just what's the mean total count because it's accumulating over time.
Just at a high level think,
I want to rise but also want it to flatten out at some point.
So that I'm getting no more incidence for that vehicle.
That's what we're seeing with a lot of these.
There's a bit of a rise and it's starting to shallow out.
If you want detailed information, you can look under each one.
We can do some fit models, I'm not going to at this point,
because we're starting near the end,
but it would be similar types of models that you would fit here.
Let's look at the SAD Group, if you will.
There's clearly a difference here.
Notice this big spike and again, that is the software discrepancy.
What we're seeing is we've essentially got a new vehicle.
You can you can clearly see if we compare that is starting out later.
We had a couple, maybe some early on while the other vehicles being tested.
Makes sense.
You got to sort of pilot group being tested.
Then when they did full scale testing, the software started having some issues.
Now it's starting to get better.
We're seeing that level out.
We saw that in the previous data.
There's clearly a difference, but they are doing better.
These two, the unwanted maneuver, the perception discrepancy,
I would say visually they're on par with what I see here.
Clearly the software is the big issue here.
What's the big takeaway here?
What would we say about this?
Well, it seems that we've got two different series of vehicles.
We've got one that they were working on for a while.
Then in 2021, they've introduced a new series of vehicles.
For right now, especially in 2021,
there is a bit of issues with the software going on.
A lot of software discrepancy issues causing incidents.
They seem to be improving that now.
That makes sense.
You've introduced something, there's going to be bugs.
Just give it some time.
All the other ones seem comparable with what was going before.
Overall, I've got a pretty good feeling about this new series.
Give it some time to burn in.
Well, I hope I've given you a flavor of all the things that JMP can do,
especially in the reliability platform as well as in preparing some of your data.
If you have any questions about this,
this journal will be available where you can find this talks.
Some of the data tables will be available there as well.
You get to play with all of this.
There are also some other graphs didn't really go into some other analyzes,
so feel free to explore.
That's what we do here to JMP statistical discovery.
If you have any questions about it,
I'll be in some of the Meet the Expert sessions so you can find me there.
I'd love to chat with you about this
or anything else you might have about designing experiments or reliability.
Thank you for your time.