Correlation coefficient +1 means -
Ans. is 'c' i.e., Very strong positive correlation o A correlation simply expresses the strength and direction of the relationship between two variables in terms of a correlation coefficient, signified by 'r'.o Values of r varies from -1 to +1.;o The strength of the relationship is indicated by the size of the coeffic ient, whereas its direction is indicated by the sign (+ or -)o A plus sign (+) means : That there is a positive correlation between the tivo variables - high values of one variable (such as salt intake ) are associated with high value of the other variable (such as blood pressure) i.e salt intake is directly proportional to blood pressure.o A negative sign (-) means : That there is a negative correlation between the two variables - high values of one variables (such as cigarette consumption ) are associated with low values of the other (such as life expectancy).Cigarette consumption is inversely proportional to life expectancyo If there is a perfect linear relationship between the two variables so that it is possible to know the exact value of one variable from the knowledge of other variable, the correlation coefficient ( r ) will be exactly + or - 1.00 ( +1 or -1 ).o If there is absolutely no relationship between the two variables so that it is impossible to know anything about one variable on the basis of knowledge of the other variable. Then the coefficient will be 0.Strength of correlationo The strength of linear relationship between two random variables X and Y is based on the value of correlation coefficient and is often summarized according to the following guide! ines:-For Positive CorrelationFor negative correlationInterpretationr < 0. 30- 0-30 < rvery weak linear relationship0-30 <r< 0.50-0-50 <r<- 0-30weak linear relationship0-50 < r < or 0.80- 0-80 < r <-0-50moderate linear relationship0-80 < r < 0.90- 0-90 <r <-0-80strong linear relationshipr >0-90r < - 0 90very strong linear relationshipo If you have difficulty in interpreting above table, I am giving in very simple language:-Positive CorrelationCorrelation coefficient less than 0[?]30 - Very weak positive correlation.Correlation coefficient 0[?]30 to 0[?]49 - Weak Positive correlationCorrelation coefficient 0[?]50 to 9[?]79 - Moderate Positive correlationCorrelation coefficient 0[?]80 to 0[?]89 Strong Positive correlationCorrelation Coefficient equal to or greater than 0.90 - very strong positive correlation.Negative CorrelationCorrelation coefficient more than - 0[?]30 - Very weak negative correlationCorrelation coefficient- 0[?]30 to - 0[?]49 -Weak negative correlationCorrelation coefficient - 0[?]50 to- 0[?]79 - Moderate negative correlationCorrelation coefficient - 0[?]80 to- 0[?]89 - Strong negative correlation.Correlation coefficient equal or less then - 0-90 - very strong negative correlationNote: you should keep in mind that for negative values, more means towards more positive side and less means towards more negative side. For example; if we are saying, more than - 0[?]30, that mean - 0[?]29, - 0[?]28, - 0 27.... so on; and if we are saying less than - 0.90 that means - 0.91, - 0.92 .... so on.
Very weak positive correlation
Moderate positive correlation
Very strong positive correlation
Strong positive correlation
Data Variables