Databases
StackOverflow2013
Postsdbo
PO
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO
    primarykey
    data
    text
    <p>As Peter says, you have to minimize a function <code>f(a,b,c)</code>. There are a lot of elaborate methods for well behaving functions. Eg for functions which can be differentiated, or for so called convex functions. In your case you have a function where we do not know very much about. So f could have different local minima which kills many established minimization methods.</p> <p>If a simple evaluation of a parameter set <code>a,b,c</code> is fast, you can try some kind of coordinate descent. This is not the best method, brute force but easy for you to implement. I will name the standard deviation achieved by <code>(a,b,c)</code> as <code>s(a,b,c)</code>:</p> <p>I give you some python style pseudo code, which should be easy to read:</p> <pre><code> def improve(a,b,c): eps = .01 s1 = s(a*(1+eps), b, c) s2 = s(a, b*(1+eps), b, c) s3 = s(a, b, c*(1+eps)) s4 = s(a*(1-eps), b, c) s5 = s(a, b*(1-eps), c) s6 = s(a, b, c*(1-eps)) # determine minimal of (s1....s6) and take index: i = argmin (s1....s6) # take parameters which lead to miminal si: if i==1: a = a*(1+eps) if i==2: b = b*(1+eps) ... if i==6: c = c*(1-eps) return a,b ,c </code></pre> <p>You have to start with some values <code>(a,b,c)</code> and this function should give you a new triple <code>(a,b,c)</code> which leads to less variation. Now you can apply this step as often as you want. Maybe you have to adapt <code>eps</code>, that depends on how fast <code>s(a,b,c)</code> changes if you make little modifications on <code>a</code>, <code>b</code>, or <code>c</code>.</p> <p>This is not the best solution, but an easy to try hands-on approach.</p>
    singulars
    1. This table or related slice is empty.
    1. POAutomatic adjustment of 3 parameters to minimize standard deviation
      singulars
      1. PTQuestion
    1. PTAnswer
    1. USealdent
    1. USrocksportrocker
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. POAutomatic adjustment of 3 parameters to minimize standard deviation
      singulars
      1. PTQuestion
    1. This table or related slice is empty.
    1. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTApproveEditSuggestion
    3. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    1. This table or related slice is empty.
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload