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?
The mean, also known as the average, is a measure of central tendency in statistics. It is calculated by adding all the values in a data set and dividing by the number of values in the set.
To find the mean, you need to add all the values in a data set and then divide by the number of values in the set. For example, if you have the data set {2, 5, 9, 12, 15}, the mean would be (2+5+9+12+15)/5 = 8.6.
Finding the mean allows us to summarize a large set of data into a single value. It gives us an idea of the typical or average value in the data set.
Outliers, which are extreme values in a data set, can significantly impact the mean. If there are outliers present, the mean may not accurately represent the data. In such cases, it may be more appropriate to use other measures of central tendency, such as the median or mode.
The mean is most commonly used for numerical data, but it can also be used for categorical data that can be assigned numerical values. However, it may not be appropriate for all types of data, such as ordinal data, where the order of values is important.