## Data Levels of Measurement (Nominal, Ordinal, Interval, Ratio) in Statistics

Data levels in statistics indicates the measurement levels in statistics. In statistics, the statistical data whether qualitative or quantitative, are generated or obtain through some measurement or some observational process. Measurement is essentially the task of assigning numbers to observations…

## Business Forecasting Definition, Steps, Modeling and Importance

Business forecasting is the process of making prediction of the future based on past and present data. In many cases a reliable forecast can be worth a lot of money, such as consistently and correctly guessing the behavior of the…

## Statistical Inference Definiton, Types and Estimation Procedures in statistics

Inference comes from a word ‘infer’ which means that to draw a conclusion about a phenomenon on the basis of some information at hand. To make inference about a phenomenon through some statistical procedure is called statistical inference. According to…

## An Intuitive Study of Time Series Analysis

Time series analysis is an impotant forcasting procedure to find the trend of time series data. It is an important statistical procedure to analyze the time trend data and make interpretation from the analysis result. According to wikipedia, “In mathematics,…

## Correlation Analysis definition, formula and step by step procedure

The relationship between two or more random variables are generally defined as the correlation. It is the major part of bivariate analysis. When variables are found to be related, we often want to know how close the relationship is. The…

## Skewness and Kurtosis in Statistics (shape of distributions)

Skewness and kurtosis are two important measure in statistics. Skewness refers the  lack of symetry and kurtosis refers the peakedness of a distribution.    Skewness Literally, skewness means the ‘lack of symmetry’. We study skewness to have an idea about…

Quadrat sampling is a classic tool for the study of ecology, especially biodiversity. It is an important method by which organisms in a certain proportion (sample) of the habitat are counted directly.  It is used to estimate population abundance (number),…

## Wilcoxon Signed Rank Test: Step by Step Procedure

The wilcoxon signed rank test determine whether the median of the sample is equal to some specified value. The Wilcoxon signed rank test utilizes both the sign of the difference as well as the magnitude of the differences, hence it…

## Run Test in statistics: Step by Step procedure

In many situation, we are interested to whether the data collected for statistical analysis is random or not. In most all statistical inference we assume that the data is in a random sample. If the randomness of a sample is…

## Sign Test: Step by Step calculations for small and large sample

The sign test is the oldest of all non-parametric tests. and it is so called as usually covert the data for analysis to a series of plus and minus sign. The test statistic consists of either the number of plus…