Sorry, an error occurred while loading the content.

Re: Algorithm for Sprint Burn Down Extrapolation

Expand Messages
• ... I like using several projections. We are not running full scrum, so I usually only have data on a weekly basis. I have projected the burn down with one
Message 1 of 11 , Jan 2, 2006
• 0 Attachment
Ron Jeffries <ronjeffries@...> writes:

> On Thursday, December 29, 2005, at 1:01:21 PM, Steven Line wrote:
>
>> One suggestion we had here is to average the burn down over the last 4
>> days and merely project that from the last actual burn down point.
>> That's very simple and makes sense.
>
>> Also, how many days of activity do you use to calculate your burn down
>> extrapolation? We were using 7 days, but are now moving to 4.
>
> I look at the line of actual data and extend it using a combination
> of what looks like a line and what my gut tells me. Either one of
> those, IMO, works better than a formula.

I like using several projections. We are not running full scrum, so I
usually only have data on a weekly basis. I have projected the burn
down with one week, two week, one month, and one quarter of data. All
of these on a plot together help call out changes in the burn rate.
One of my recent victories was getting a team to see that we were in
trouble and then watching them brutally cut scope until we were back
on track.

-jla

--

jalmeter under 99 at yahoo
• ... Well, in a quarter, you should be done. ;- I d be interested to see one of your charts to get a sense of what they look like and how they call out changes
Message 2 of 11 , Jan 2, 2006
• 0 Attachment
On Monday, January 2, 2006, at 8:52:01 AM, Jason Almeter wrote:

> I like using several projections. We are not running full scrum, so I
> usually only have data on a weekly basis. I have projected the burn
> down with one week, two week, one month, and one quarter of data. All
> of these on a plot together help call out changes in the burn rate.
> One of my recent victories was getting a team to see that we were in
> trouble and then watching them brutally cut scope until we were back
> on track.

Well, in a quarter, you should be done. ;->

I'd be interested to see one of your charts to get a sense of what
they look like and how they call out changes in the burn rate.

I'd also be interested in understanding why there are substantial
changes in the burn rate ...

Ron Jeffries
www.XProgramming.com
Perhaps this Silver Bullet will tell you who I am ...
• Here s one simple approach: If you are charting your burndown on an Excel chart, right-click on the data plot line and select Add Trendline to show a simple
Message 3 of 11 , Jan 3, 2006
• 0 Attachment

Here’s one simple approach:  If you are charting your burndown on an Excel chart, right-click on the data plot line and select “Add Trendline” to show a simple least-squares fit. It will extrapolate that fit line to the end of the chart, i.e. the number of plat point on the X axis.  -- Dave

From: scrumdevelopment@yahoogroups.com [mailto: scrumdevelopment@yahoogroups.com ] On Behalf Of Mark Striebeck
Sent: Thursday, December 29, 2005 10:12 AM
To: scrumdevelopment@yahoogroups.com
Subject: [Norton AntiSpam] Re: [scrumdevelopment] Algorithm for Sprint Burn Down Extrapolation

So far, I stayed away from any extrapolation. I draw the ideal burndown line and then the actual burndown rate. The trend is usually clear. It doesn't give us an exact measure (aka we will be 1.5 days late) but it's enough to make the team aware if corrections are needed.

MarkS

On 12/29/05, Steven Line <sline@...> wrote:

Hi -

We just started using Scrum a couple of weeks ago.  To calculate our
projected burn down we're using a 7 day linear regression algorithm.
The resultant projected burn down line is trying to replicate the line
of the past 7 days instead of merely project where it's currently
headed  (imagine an actual burn down that curves).  If there's an
upswing then a downswing in our actual burn down, the extrapolated burn
down will actually jog upwards then downwards, which while
mathematically correct for a regression, isn't communicating that the
team is actually burning down, not backing up.

What formula or algorithm do you use out there in scrum land?

One suggestion we had here is to average the burn down over the last 4
days and merely project that from the last actual burn down point.
That's very simple and makes sense.

Also, how many days of activity do you use to calculate your burn down
extrapolation?  We were using 7 days, but are now moving to 4.

Thank You,
Steve

To Post a message, send it to:   scrumdevelopment@...
To Unsubscribe, send a blank message to: scrumdevelopment-unsubscribe@...

YAHOO! GROUPS LINKS

• Just like Ron I d be interested to learn more about your approach. I don t understand how looking at more then one week gives you information about successful
Message 4 of 11 , Jan 3, 2006
• 0 Attachment
Just like Ron I'd be interested to learn more about your approach. I
don't understand how looking at more then one week gives you
information about successful completion of a sprint/iteration. But
then, where Ron is stubborn, I am Dutch so that may explain it :-)

--Hubert

On 1/2/06, Ron Jeffries <ronjeffries@...> wrote:
> On Monday, January 2, 2006, at 8:52:01 AM, Jason Almeter wrote:
>
> > I like using several projections. We are not running full scrum, so I
> > usually only have data on a weekly basis. I have projected the burn
> > down with one week, two week, one month, and one quarter of data. All
> > of these on a plot together help call out changes in the burn rate.
> > One of my recent victories was getting a team to see that we were in
> > trouble and then watching them brutally cut scope until we were back
> > on track.
>
> Well, in a quarter, you should be done. ;->
>
> I'd be interested to see one of your charts to get a sense of what
> they look like and how they call out changes in the burn rate.
>
> I'd also be interested in understanding why there are substantial
> changes in the burn rate ...
>
> Ron Jeffries
> www.XProgramming.com
> Perhaps this Silver Bullet will tell you who I am ...
>
>
> To Post a message, send it to: scrumdevelopment@...
> To Unsubscribe, send a blank message to: scrumdevelopment-unsubscribe@...
> Yahoo! Groups Links
>
>
>
>
>
>
>
Your message has been successfully submitted and would be delivered to recipients shortly.