Correlation Coefficient Of Correlation Between Two Variables, X And Y

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correlation coefficient. Unit 3. The Pearson product moment correlation is the most frequently utilized measure of relationships (Salkind, 2012). The symbol for this relationship is the letter r which represents the variables being correlated. Furthermore, the symbol rxy characterizes a correlation between two variables, X and Y. When computing a correlation, one requires a pair of scores, for example, reading scores and math scores for each group the researcher is working with. In the case of computing the correlation between the hours a group studies and test scores, one should measure the number of hours spent and the results of test for each individual. A good way to represent the findings is the use of scattergram, also known as scatter plot. Scattergrams provide a visual depiction of the correlation coefficient of the relationship between two variables, X and Y. They are very beneficial for researchers to determine correlation coefficients. Essentially, a correlation is a measure of how two different variables relate to one another, how they co-relate. A scattergram shows that co-relation on a diagram. The scattergram is like a graph or a bar chart, having a x and y at right angles to one another. In this case, the x axis represents one variable, while the y axis represents the second variable. The points on the scattergram are obtained by taking related measurements of the two variables. They might be related by being taken at the same time, or by coming from the same research participant, or in some other way; but they always represent a pair of scores. Each of these paired measurements is plotted on the scattergram, using a cross or an asterisk. It is not necessary to join up the points with lines, because t... ... middle of paper ... ... such a way that it would form the long axis of an oval which encompasses most of the scores. The closer a correlation is to being perfect, the more closely the more closely the scores will seem to be clustered around the line of best fit. Finally, patterns displayed in scattergrams that have stronger formations and the more a pattern aligns itself to a 45 degree angle, either from the lower left corner of the graph to the upper right corner for positive correlations, or from the upper left corner of the graph to the lower right corner for negative correlation, the stronger the visual evidence of the existence of a relationship between two variables. Scattergrams are exceptionally useful for providing a quick, visual summary of the strength of a correlation. However, they serve as an accompaniment to more complex statistics, not as an end in themselves.

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