
Advanced Statistics Advanced Probability and Statistics Math Forum 
 LinkBack  Thread Tools  Display Modes 
December 3rd, 2016, 01:52 AM  #1 
Member Joined: Aug 2014 From: Mars Posts: 88 Thanks: 8  Comparisons
Class has gotten to me. I can't get a hold of my teacher over the weekend so I'm hoping you guys can understand my question. There is this equation: $\displaystyle \sum c^2 = \left ( 1 \right )^{2} + \left ( 1 \right )^{2}$ that I don't understand why the second one is negative. Each number is supposed to represent a group. So if I were to compare one group to two groups I would should do this equation: $\displaystyle \sum c^2 = \left ( 1 \right )^{2} + \left (\frac{1}{2} \right )^{2} + \left (\frac{1}{2} \right )^{2}$ Why is the negative number there? I get the feeling that the question is out of context, let me know what you need from me to clarify. 
December 3rd, 2016, 11:21 AM  #2 
Senior Member Joined: Sep 2015 From: CA Posts: 1,238 Thanks: 638 
if I saw $\sum c^2 = (1)^2 + (1)^2$ my immediate interpretation would be that $c \in \{1,~1\}$ without further context I don't know what we can tell you. 
December 4th, 2016, 01:59 AM  #3 
Member Joined: Aug 2014 From: Mars Posts: 88 Thanks: 8 
It's for psychology. The first equation is based on two groups of people only. The second equation is one group being compared to two groups.


Tags 
comparisons 
Thread Tools  
Display Modes  

Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
Multiple comparisons problem  FatTwin  Probability and Statistics  5  April 20th, 2016 01:01 AM 
Quantitative Comparisons  nyuviolets  Algebra  5  July 27th, 2015 04:23 AM 
Please help me with multiple comparisons  urgent  mintsharpie  Advanced Statistics  0  February 10th, 2013 10:08 PM 
Expected number of comparisons in an algorithm  restin84  Computer Science  6  October 14th, 2012 02:17 PM 
number of comparisons  sangfroid  Computer Science  2  November 6th, 2007 05:05 PM 