Meaning: -- If two quantities vary in such a way that movement in one are accompanied by movement in other, these quantities are correlated. For example, there exits some relationship between age of husband and age of wife, price of commodity and amount demanded etc. The degree of relationship between variables under consideration is measured through correlation analysis. The measure of correlation called correlation coefficient. Thus,

Correlation analysis refers to the statistical techniques used in measuring the closeness of the relationship between variables.

Definition: -- According to Simpson & Kafka, “Correlation analysis deals with the association between two or more variable.”
According to Ya Lun Chou, “Correlation analysis attempts to determine the degree of relationship between variables.”
Thus correlation is a statistical device, which helps us in analysis the co-variation of two or more variables.
The problem of analysis the relation between different series should be broken down into 3 steps: - 1. Determining whether a relation exists & if it does, measuring it. 2. Testing whether it is significant.

3. Establishing the cause & effect relation, if any.

It should be noted that detection & analysis of correlation (i.e., co variation) between two statistical variables requires relationship of some sort, which associates the observation in pairs, one of each pair being a value of each of two variables. In general, the pairing relationship may be of almost any nature, such as observation at the time or place or over a period of time or different places.

SIGNIFICANCE OF THE STUDY OF CORRELATION

The study of correlation is of immense use in statistical analysis & practical life because of following reasons: -- 1. Shows Relationship: -- Most of variables show some kind of relationship. For example, there is relationship between price & supply, income & expenditure etc. Through correlation...

...Correlationanalysis:
The correlationanalysis refers to the techniques used in measuring the closeness of the relationship between the variables. The degree of relationship between the variables under consideration is measured through the correlationanalysis. And the measure of correlation called as correlation coefficient or correlation index summarizes in one...

...The Spearman Correlation Coefficient remains one of the most important nonparametric measures of statistical dependence between two variables. The Spearman Correlation Coefficient facilitates the assessment of two variables using a monotonic function. This representation is only possible if the variables are perfect monotones of each other and if there are no repeated data values. This enables one to obtain a perfect Spearman correlation of either +1...

...14: Correlation
Introduction | Scatter Plot | The Correlational Coefficient | Hypothesis Test | Assumptions | An Additional Example
Introduction
Correlation quantifies the extent to which two quantitative variables, X and Y, “go together.” W hen high values of X are associated with high values of Y, a positive correlation exists. W hen high values of X are associated with low values of Y, a negative correlation exists. Illustrative data...

...Project 1: Linear Correlation and Regression Analysis
Gross Revenue and TV advertising:
Pfizer Inc, along with other pharmaceutical companies, has begun investing more promotion dollars into television advertising. Data collected over a two year period, shows the amount of money Pfizer spent on television advertising and the revenue generated, all on a monthly bases.
|Month |TV advertising |Gross Revenue |
|1 |17...

...Understanding the Pearson Correlation Coefficient (r)
The Pearson product-moment correlation coefficient (r) assesses the degree that quantitative variables are linearly related in a sample. Each individual or case must have scores on two quantitative variables (i.e., continuous variables measured on the interval or ratio scales). The significance test for r evaluates whether there is a linear relationship between the two variables in the population. The...

...What is Correlational Research?
The correlation research method is appropriate when researchers want to study and “assess relationships among naturally occurring variables.” Assessment means making predictions about the nature of the relationships being studied. It also means describing the relations and assigning them a “correlation coefficient” that describes the direction and magnitude of the movement of variables to one another.
There are many types of...

...scatter diagram made by the given data, it is noted that as the disposable income increases the annual sales also increases.
[pic]
➢ Again, We know that the coefficient correlation is,
r = [pic][pic]
Here,
r = [pic]
= [pic]
= 0.70
Therefore, there is a strong positive correlation between the disposable income and the annual sales.
➢ The regression coefficient is 0.193. That means sales will increase by $0.193...

...chosen randomly out of 500 Omani families.
Different types of statistical analysis were applied on the sample e.g. measures of location and dispersion as well as using graphical and tabular methods to represent data.
METHODS :
A simple random sample of 50 households were selected and a number of statistical analysis were done.
1-numirecal methods:
(table 1,numerical analysis)...