Data analysis

Types of Data Analysis

Analysis involves estimating the values of unknown parameters of the population and testing hypothesis for drawing inferences. Types of Analysis a. Qualitative analysis b. Content analysis c. Quantitative analysis d. Descriptive analysis e. Bivariate analysis f. Sequential analysis g. Casual analysis h. Multivariate analysis i. Inferential analysis j. Statistical analysis Qualitative Analysis It is less influenced by theoretical assumption. The …

Important properties of the Normal distribution

The normal distribution was first described by Abraham Demoivre (1667-1754) as the limiting form of binomial model in 1733. Normal distribution was rediscovered by Gauss in 1809 and by Laplace in 1812. Both Gauss and Laplace were led to the distribution by their work on the theory of errors of observations arising in physical measuring processes particularly in astronomy. Here …

Multivariate normality Tests with R – Mardia’s Test, Henze-Zirkler, Royston

Most multivariate techniques, such as Linear Discriminant Analysis (LDA), Factor Analysis, MANOVA and Multivariate Regression are based on an assumption of multivariate normality. So, In this post, I am going to show you how you can assess the multivariate normality for the variables in your sample. The above test multivariate techniques can be used in a sample only when the …

Measurement Scales–Nominal, Ordinal, Interval and Ratio

Measurement scales are classified popularly under four categories: Nominal, Ordinal, Interval, Ratio. Let’s discuss in brief about these measurement scales before going on for some technical details. If you want to test Network of 50 smart phone users. Let’s begins by evaluating each on 4G – Non 4G data; this is a nominal measurement. Then the users ranks the Quality …

Common symbols used in statistical tests

Each statistical tests or methods has its own terminology and symbols, but the following are commonly used by all statisticians / researchers N – Size of population n – number of observations (sample size) K – number of samples (each having n elements) α (Alpha) – level of significance v (Nu)- degrees of freedom σ (Sigma)- standard deviation (population) s …

What’s new in Gretl2017a

Gretl is a free and open source package for econometric analysis on 15-04-2017 updated version gretl2017a was released. The following are the new features, bug fixes and change log of new version. Improved parsing for the member-of relation, on both the left- and right-hand side of hansl statements Calendar: ensure that the Gregorian calendar is used consistently but add some …