Correlational Approach Final Version

The Correlational Approach MSA

Introduction 

There are several types of research studies.

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All research studies can be classified under two main categories: the qualitative versus the quantitative.

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Introduction 

The qualitative approach involves the collection of narrative data in order to gain insights into a phenomenon of interest; data analysis includes the coding of the data and production of verbal synthesis (inductive process). e.g. Historical Research

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Introduction  The

quantitative approaches involve the collection of numerical data in order to explain, predict and/or control a phenomenon of interest; data analysis is mainly statistical (deductive process).

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Introduction 

Such as: -The Correlational Research -The Experimental Research

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The Correlational Research Definition: 

The correlational research attempts to determine whether and to what degree, a relationship exists between two or more quantifiable (numerical) variables.

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The Correlational Research 

You collect data on at least two variables for the same group of subjects and then calculate a correlation coefficient between the two variables.

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What is a Correlation Coefficient? A correlation coefficient is a number between -1 and 1 which measures the degree to which two variables are linearly related. 

It is represented by the letter (r).

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What is a Correlation Coefficient? 

If there is perfect linear relationship with positive slope between the two variables, we have a correlation coefficient of 1. r=1

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If there is positive correlation, whenever one variable has a high (low) value, so does the other.

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What is a Correlation Coefficient? If there is a perfect linear relationship with negative slope between the two variables, we have a correlation coefficient of -1. r = -1  If there is negative correlation, whenever one variable has a high (low) value, the other has a low (high) value. 

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What is a Correlation Coefficient? 

A correlation coefficient of 0 means that there is no linear relationship between the variables (null). r=0

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What is a Correlation Coefficient?  To

understand what is a correlation coefficient, follow these links and move the curser:

http://noppa5.pc.helsinki.fi/koe/flash/corr/corrx2-en.html http://noppa5.pc.helsinki.fi/koe/corr/cor7a/cor7a.html

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What is a variable? Variable: a defined characteristic that varies; it has at least two values and usually more. 

For example, anxiety about writing in a second language is a variable, because it varies across students.

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What is a measure? 

To assign a value to the degree of anxiety that students feel, they are given a test (measure) of writing anxiety.

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Examples of Correlational Research 

The relationship between intelligence and selfesteem

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The relationship achievement

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The relationship between using an aptitude test and predicting success in an algebra course

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anxiety

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Examples of Correlational Research 

A group of high school students took two tests that required them to solve analogies to recognize antonyms (relationship).

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The researchers discovered a correlation between students’ abilities to complete analogies correctly and to identify antonyms.

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Examples of Correlational Research 

In general, students who were good at one task were also good at the other; students weak in one task were weak in the other.

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An Important Note In correlational research, no attempt is made to state that one thing causes another, only that one thing (one variable) is predictable from the other.

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Validity 

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A measure (test) is valid if it measures what it is intended to measure. To demonstrate the validity of a test we want to show that scores on the test correlate highly with some external measure of what the test purportedly measures. This external measure is referred to as the criterion. Dalia Mostafa

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Reliability 

The reliability of a measure refers to the accuracy or consistency of the measurement.

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There are many sources of error that can reduce the accuracy of measurements.

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Reliability 

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In such cases, it is important to provide evidence that the observations or ratings are reliable. This is accomplished by determining interrater reliability, sometimes called interobserver reliability or interjudge reliability.

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Reliability 

To do this, two or more persons rate the same phenomenon.

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Their ratings are then compared to see how well they agree with one another.

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Recap The

Qualitative & Quantitative approaches

The

definition of the correlational research

The

definition of the correlational coefficient: Positive, Negative & Null

What

is a variable?

What

is a measure?

The 08/03/09

validity & reliability of a correlational research Dalia Mostafa

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