So in trying to visualize this decay, is it safe to make the following
assumptions in terms of associating these input values to a graph:
origin is the start (x-value) of the slope, in this case the date
9/17/2013
for all points up to offset, the slope is flat, so there's no negative
scoring for the 5 days after 9/17/2013
the "end" of the slope is scale
at the data point 'scale', the slope will have a y-value (on the graph)
of decay (0.5)
The last point I am not so sure about. Furthermore, I'm unclear as to what
happens for articles outside of scale, so past 10 days. My test show that
they actually get a 'zero' multiplier for their score, so basically their
scores all end up being zero. I was under the impression that they would
get a score multiplier of 0.5. Any help would be appreciated.
I added an image which hopefully explains a little better how decay
functions work here:
origin is the start (x-value) of the slope, in this case the date 9/17/2013
yes
for all points up to offset, the slope is flat, so there's no negative scoring for the 5 days after 9/17/2013
The decay function never returns a negative value. It will always be
between 0 and 1. For each value within +- offset from the defined
origin the decay function will just return 1.
the "end" of the slope is scale
No, decay function will decrease further. The scale parameter just
steers how quickly the function approaches 0.
at the data point 'scale', the slope will have a y-value (on the
graph) of decay (0.5)
yes.
My test show that they actually get a 'zero' multiplier for their score, so basically their scores all end up being zero. I was under the impression that they would get a score multiplier of 0.5.
No, the score will decrease further until it reaches 0. If you need
to have documents outside the "scale" range to have a value of 0.5 you
need to define a separate function which then adjusts the score for
these documents as needed.
On Thu, Nov 6, 2014 at 8:07 PM, Marlo Epres mepres@gmail.com wrote:
I've begun using the decay function in order to promote more recent results
in our index. In particular I'm using what's documented here:
So in trying to visualize this decay, is it safe to make the following
assumptions in terms of associating these input values to a graph:
origin is the start (x-value) of the slope, in this case the date
9/17/2013
for all points up to offset, the slope is flat, so there's no negative
scoring for the 5 days after 9/17/2013
the "end" of the slope is scale
at the data point 'scale', the slope will have a y-value (on the graph) of
decay (0.5)
The last point I am not so sure about. Furthermore, I'm unclear as to what
happens for articles outside of scale, so past 10 days. My test show that
they actually get a 'zero' multiplier for their score, so basically their
scores all end up being zero. I was under the impression that they would get
a score multiplier of 0.5. Any help would be appreciated.
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