Green Line on Weight Chart

Can somebody explain what the green line on the CC weight chart represents?  A little confused....

Yeah, that's a great question. I'm totally confused by that, too.  What the heck is the "trend" anyway?  I've looked in the everywhere for an answer and couldn't find one. 

I don't know the exact calculation that it uses, but the idea is to account for normal fluctuations in your weight.  So while your weight may jump up or down a few pounds a day, the "trend line" is supposed to smooth things out and give you a better idea of your real progress.

Bah and humbug!

If I am down 2 pounds I don't want some green line sucking all the fun out of it!

doomie, is that true?  i thought it was the pace at which you'd have to lose weight to reach your goal by X date. 

http://www.calorie-count.com/forums/post/4755 6.html

CC takes into consideration an average of 1.5 pounds a week weight loss. So if you loose more, there would be a big gap between your current trend and the ideal trend. Hope this helps.

caloriecountingme ~ Yep, it's a smoothed-out version of your progress.  So if your line is looking like the pace you need to be on to meet your goal, then you must be doing good!!!

kay_h ~ down 2 pounds might take the fun away... but when you go UP 2 pounds, the green line is your friend!!!

The green line is a "moving average", a standard statistical technique for reducing the effects of measurement noise and of random variations in the thing being measured.  The "trend weight" on any given day is the average of your weights across the 10 most recent entries ending on that day.  In the terminology used here, it's a "prior moving average with n=10".

So, for example, if you log your weight here every day, then your "trend weight" on 22 September is the average of the weights you entered on each of 22 September, 21 September, ..., and 13 September -- the 10 most recent weight entries ending on 22 September.  Any weights you entered before 13 September are irrelevant.

If you lose weight every day, your trend weight will always be higher than your current weight (because it's always "averaging in" 9 days when you weighed more than today).  Similarly , if you gain weight every day, your trend weight will always be lower than your current weight.

But essentially nobody loses (or gains) scale weight every day.  In particular, fluctuations in water weight alone can routinely amount to several pounds up or down each day (less so if you're male and/or stay fully hydrated), and a moving average is an effective way to "smooth out" that random "noise".

tgpish, your explanation was helpful.  is the green line/"moving average" a chart of each day's "trend weight," then?  (does it siphon out the "noise" the same way the trend weight does?)

Right!  The blue line is a graph of the weights in the "Weight" column, and those are the weights you entered by hand.  The green line is a graph of the weights in the "Trend" column, which is a computed moving 10-day average of the weights in the "Weight" column.

I don't know what your chart looks like, but for most people the green line is "smoother" (fewer sharp changes in direction) than the blue line.  In theory, that's because rapid changes in direction are due to random factors (like daily water weight), and a moving average is usually effective at filtering relatively small random fluctuations away.