Linearly Weighted Moving Average

Categories: Metrics, Investing

See: Moving Average - MA.

Not to be confused with an exponential moving average because, well, they have different names, so there’s a good chance (like 100%) that they’re different things.

A linearly weighted average is like a normal moving average, except that a linearly weighted moving average adds weight to more recent entries in a moving average, rather than giving each entry an equal weight in the arithmetic average.

Let’s say we had the following data on our Ugli Fruit harvest taken over a six-day period:

12, 14, 11, 10, 16, 18.

A regular moving average (using groups of three) would add up the first three values (12 + 14 + 11 = 37) and divide that value by three, giving us our first moving average of 12.33.

A linearly weighted moving average would multiply each of the same three entries by a weight with the most recent value getting the highest weight. Weights are usually numbered from one up to the number of entries.

That gives us (12 x 1) + (14 x 2) + (11 x 3) = 12 + 28 + 33 = 73. We then divide by the sum of the weights (1 + 2 + 3 = 6), which gives us 12.17.

Naturally, for both moving averages (the normal one and the linearly weighted one), we’d then move one entry down the line and calculate the next moving average, and repeat that until we reached the end of the data.

So think of a linearly iterated curve as one with a generally straight line; an exponent has curves. Teeter-totters versus the double black diamonds at a top-notch ski resort.

Related or Semi-related Video

Finance: What are moving averages?7 Views

00:00

Finance a la shmoop... what are moving averages? ooh I need another tissue that [Girl crying]

00:09

average I just can't get enough so moving okay yeah yeah that's not at all

00:13

what this term is about here's a chart here's a set of trailing averages 50-day

00:18

the blue line they're hundred-day the black line and 200-day the green line

00:22

there... note that we say trailing average why trailing? well people we lost our

00:29

crystal ball yeah Warren we know you took it [Warren Buffett eating dinner]

00:31

so averages for normal humans can only be trailing because trailing stockticker

00:37

closing prices give us data we can actually use stock averages don't take

00:42

future data that we're merely guessing at on their charts... only

00:46

real numbers that we can actually point to so here's the 50-day average for [50-day average for coca cola stock]

00:50

coca-cola stock KO in 2012 and if we move forward a year and change well here

00:56

it's a 50-day average right there looks a little bit different and while the 50

01:00

data input elements from its closing price each day vary so the average of

01:06

those data points will move and why do moving averages matter well for

01:11

fundamental analysts kinds of investors you know the people who care just about [Fundamental analyst people appear]

01:14

the cash flow and earnings and margins and revenue growth of companies well

01:17

really don't matter but for chartist types of investors that is those who

01:22

focus really only about trading trends and shapes and curves and the metrics

01:27

behind what patterns of stocks take in the future well, they matter a lot then

01:32

in fact the 200-day moving average is generally a kind of Chartist living [Priests in church]

01:37

Bible for most Wall Street traders and taking meaning from it is all about

01:41

recognizing patterns and then imputing likely future patterns based off of

01:46

those shapes for example if you're looking here at the peak of a Head and [Head and shoulders stock price graph]

01:51

Shoulders chart, the trailing average of this

01:55

say 50-day set here of data points is the line about here but if you move

02:01

forward and look at the back half well then the moving average is about here [Moving average lines moves]

02:06

and if you consider the entire chart well it's about here and the lines are

02:10

there in theory to give color as to what direction the

02:13

market or this given stock is heading and yep sometimes it works and sometimes

02:18

it doesn't [Man eating dinner with Warren Buffett]

Find other enlightening terms in Shmoop Finance Genius Bar(f)