Degrees of Freedom denotes the number of samples that a statistician has the freedom to choose. Degrees of Freedom is based on a concept that one could not have exercised his /her freedom to select all the samples.
The concept can be explained by an analogy:
X+Y = 10 (1)
In the above equation you have freedom to choose a value for X or Y but not both because when you choose one, the other is fixed. If you choose 8 for X, then Y has to be 2. So the degree of freedom here is 1.
X+Y+Z = 15 (2)
In the formula (2), one can choose values for...
Web Analytics Terms
A
Abandonment: is the measure when a visitor exits or leaves a conversion process on a website and does not return later during the session.
A/B Testing: A method of banner ads, emails and landing pages testing by which a baseline control sample is compared to a variety of single-variable test samples.
Accuracy: The ability of a measurement to match the actual value of the quantity being measured. Accuracy is the foundation upon which your web analytics should be built. If you can't trust that your data is accurate, you can't make...
Statistics Formulas
Notation
Capitalization
In general, capital letters refer to population attributes (i.e., parameters); and lower-case letters refer to sample attributes (i.e., statistics). For example,
- P refers to a population proportion; and p, to a sample proportion.
- X refers to a set of population elements; and x, to a set of sample elements.
- N refers to population size; and n, to sample size.
Greek vs. Roman Letters
Like capital letters, Greek letters refer to population attributes. Their sample counterparts, however, are usually Roman letters. For...