[Year 12 IT Apps] information needed for gantt charts

[Mark Kelly]

PARAGREEN, Chris wrote:
> My first post as a newbie IT teacher!

Welcome!

> “Just” a question about some of the definitions for Gantt charts….
> 
> According to Potts (p30), lead time is, “… time leading up to or before 
> a task.” It further explains the concept, but essentially this is it.
> 
> My understanding is that lead time is the time available to begin a 
> dependant task before its predecessor is finished.
> 
> For example, you can’t set up a computer until the box has arrived, but 
> you can prepare the room in advance.

Yes, that's how I understand it too.  While, strictly speaking, a 
dependent task cannot begin until its predecessor ends, in the real 
world it's sometimes possible to start a little early.

> Similarly, Potts states that slack time and lag time are the same thing, 
> whereas I think they are not.
> 
> Slack is the available time to allow for delays, but lag is the time 
> between when a task finishes and when it’s dependant task can begin.

Yes.  Slack is the time difference between two concurrent tasks of 
unequal duration.

> For example, if pouring concrete, the actually pouring task might have 
> finished, but you have to wait for the concrete to cure (the lag time) 
> before you can paint it.

That's how I understand it too.  Slack is not lag.
> 
> Are my definitions too precise for what we need to teach, am I wrong, or 
> am I missing something?

Nope.  We agree.  It's worth mentioning it to the kids, but don't bust a 
gasket over it.  The exam has never assessed lag or lead time before, 
The most complex it got has been having a dummy task once (which, by the 
way, it got wrong!)

Cheers!
Mark

> 
> Regards,
> 
>  
> 
>  
> 
> Chris Paragreen
> 
> IT, Mathematics and Japanese Teacher and Timetabler
> 
> Kew High School
> 
> 1393 Burke Road
> 
> Kew East VIC 3102
> 
> phone +613 9859 8652 fax +613 9819 7880
> 
> chris.paragreen at kew.vic.edu.au <mailto:chris.paragreen at kew.vic.edu.au>
> 
> *2008 International Year of Languages *
> 
> *Languages Still Matter! *
> 


-- 
Mark Kelly
Manager - Information Systems
McKinnon Secondary College
McKinnon Rd McKinnon 3204, Victoria, Australia
Direct line / Voicemail: 8520 9085
School Phone +613 8520 9000
School Fax +613 9578 9253
kel at mckinnonsc.vic.edu.au

Webmaster - http://www.mckinnonsc.vic.edu.au
IT Lecture notes: http://vceit.com
Moderator: IT Applications Mailing List

RealMenDon'tNeedSpacebars.