My Math Forum  

Go Back   My Math Forum > College Math Forum > Advanced Statistics

Advanced Statistics Advanced Probability and Statistics Math Forum

Thanks Tree1Thanks
  • 1 Post By romsek
LinkBack Thread Tools Display Modes
December 3rd, 2016, 12:52 AM   #1
Senior Member
Joined: Aug 2014
From: Mars

Posts: 101
Thanks: 9


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.
Opposite is offline  
December 3rd, 2016, 10:21 AM   #2
Senior Member
romsek's Avatar
Joined: Sep 2015
From: USA

Posts: 1,980
Thanks: 1027

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.
Thanks from topsquark
romsek is offline  
December 4th, 2016, 12:59 AM   #3
Senior Member
Joined: Aug 2014
From: Mars

Posts: 101
Thanks: 9

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.
Opposite is offline  

  My Math Forum > College Math Forum > Advanced Statistics


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 09:08 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 04:05 PM

Copyright © 2018 My Math Forum. All rights reserved.