Stat Cache Traditional Geocache
TeamBlunder: Moving. Thanks to those who have found this one.
TeamBlunder
-
Difficulty:
-
-
Terrain:
-
Size: 
(micro)
Please note Use of geocaching.com services is subject to the terms and conditions
in our disclaimer.
THE ABOVE COORDINATES ARE FALSE YOU MUST SOLVE A PROBLEM TO FIND THIS CACHE.
There has been a lot of talk in Arizona cache circles about Geocaching Stats and a type of cache that has been dubbed a Stat Cache. I thought it would be interesting and fun to lay out a Stat Cache that involves using an actual elemetary Descriptive Statistics method to solve for the coordinates of the cache.
BACKGROUND: THE Z-TRANSFORM
For normally distributed data, we can use the Z-Transform to determine the proportion of a product that falls within a specific range based on that product's mean (average) and Sigma - standard deviation.
The Z-Transform has the GENERAL form of Z = (x-u)/Sigma where:
Z = The number of standard deviations (Sigmas) from the mean.
x = the range that you are interested in.
u = the mean (average) measurement.
Sigma = the standard deviation of the measurements.
This method can be used to estimate yield for a process using the above parameters
SOLVING FOR THE Z-VALUE:
Determine the estimated yield (the estimated percentage of GOOD product) given that 150 measurements were made of a product reulting in:
Mean = u = 1.03
Sigma = Standard Deviation = 0.0573
the specifications are
Lower Specification Limit (LSL) = 0.90
Upper Specification Limit (USL) = 1.10
You are solving for the estimated % GOOD - EXAMPLE if 25% is out of the specifications 75% is GOOD
TO SOLVE FOR THIS YIELD USING THE Z-TRANSFORM YOU WILL NEED A Z-TABLE. YOU CAN FIND A Z-TABLE IN ANY INTRODUCTORY STATISTICS BOOK, THEY ARE ON-LINE OR YOU CAN e-mail ME AT joenveng@cableaz.com for a Z-Table in POWERPOINT FORMAT. You will have to interpolate the answer using this table. If you don't know how to interpolate, e-mail me, I can tell you how. AN INTRODUCTORY STATISTICS TEXTBOOK WILL WALK YOU THROUGH HOW TO SOLVE FOR THIS PROBLEM, or again, you can just e-mail me for help.
Solving for the Coordinates:
The North Coordinates are false
The West Coordinates are true (the actual W coordinates for the cache).
To solve for the North Coordinates take your answer Rounded to the nearest 3rd digit (39.42% becomes 39.4%) and express as a decimal (39.4 becomes .394), MULTIPLY this number times 3 (.394 x 3 = 1.182) and SUBTRACT from the N minute coordinates (using 1.182 the N coordinates would be 24.308 - 1.182 or 23.126 and thus N33 23.126
Due to rounding errors it it is possible to solve correctly and not get the exact coordinates of the cache. Therefore I suggest you e-mail me your answer before you go search for the cache...if it is anywhere close I will give you the exact coordinates.
The cache itself, in true nature of a Stat Cache is an Altoids tin hidden in an ALMOST drive by fashion.
Additional Hints
(Decrypt)
Erzrzore, vg'f whfg zngu. Qba'g trg sehfgengrq whfg r-znvy zr, V jvyy or zber guna unccl gb uryc lbh va nal jnl gung V pna.<p>
Gb fbyir guvf lbh jvyy unir gb fbyir gur tvira rdhngvba gjvpr ol fhofgvghgvat gur YFY naq gur HFY frcrengryl sbe k. Gurer ner zber fgrcf, ohg gung fubhyq trg lbh fgnegrq.<p>
Gur nafjre lbh trg jvyy qrcraq ba gur M-Gnoyr gung lbh hfr. Fbzr M-gnoyrf ner rkpyhfvir...va gung pnfr lbhe nafjre jura lbh fbyir vg jvyy or gur % "onq". Bgure M-gnoyrf tvir gur nafjre va n phzzhyngvir be haqre gur pheir sbez...va gung pnfr vg jvyy tvir lbh gur % tbbq.