The discussion revolves around calculating the mean of a set of x values and understanding related statistical concepts such as Sxx and Sxy. The values provided are part of a dataset where x ranges from -5 to 5, and corresponding y values are given. Participants are exploring how to compute the mean and its implications for further calculations.
Some participants have provided guidance on calculating the mean as the arithmetic average, while others are discussing the relationship between mean and median in this context. Multiple interpretations of the terms used are being explored, particularly regarding the variability of the x values.
There is a noted confusion about the calculation of the mean due to the specific values of x, which sum to zero. The discussion also touches on the definitions of mean and median, with participants clarifying their meanings in this scenario.
Fairy111 said:Homework Statement
From the data:
x=-5 -4 -3 -2 -1 0 1 2 3 4 5
y= 1 5 4 7 10 8 9 13 14 13 18
These values are in a table, ie -5 corresponds to 1, -4 to 5 and so on.
I have to find:
Sxx=Sum of [x(i) - mean of x]^2
Sxy=Sum of [x(i) - mean of x][y(i) - mean of y]
Im not sure how to do this. Whats the mean of x?
Homework Equations
The Attempt at a Solution
HallsofIvy said:It is true here that you x values form an arithmetic sequence with an odd number of values: and the mean of such a sequence is the middle value.
In this situation the mean and the median are the same.microguy said:Did you mean Mean or Median?