Data Analysis Lecture 5 Correlation PDF
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Uploaded by RefreshingManticore7704
Shaheed Benazir Bhutto Women University
Dr Sonia Shagufta
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Summary
This document is a lecture on data analysis, focusing on correlation. It covers different types of correlations, such as Pearson's r, Spearman's rho, and Kendall's tau, and explains how to interpret the results of correlations in SPSS. The lecture also touches on the concepts of one-tailed vs. two-tailed tests and the assumptions of different correlation methods.
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Data Analysis Lecture 5 Correlation Dr Sonia Shagufta Correlation Correlation Pearson’s r Spearman’s rho Kendall’s tau Point-biserial Partial correlations Correlations What is a correlation? A relations...
Data Analysis Lecture 5 Correlation Dr Sonia Shagufta Correlation Correlation Pearson’s r Spearman’s rho Kendall’s tau Point-biserial Partial correlations Correlations What is a correlation? A relationship between two variables E.g. As one gets older ------> wisdom When one increases the other increases (positive correlation) When one increases the other decreases (negative correlation) We get to test if these are significant relationships using the correlations of SPSS Correlations Different types of correlations Pearson’s correlation Pearson’s r Spearman’s rho Spearman’s rs Kendall’s tau Kendall’s τ Referred to also as ‘bivariate’ correlations Pearson’s r Dataset Exam Anxiety Analyze -> Correlate -> Bivariate Exam performance, exam anxiety, time spent revising Choose Pearson’s correlation One-tailed or two tailed? Directional versus non-directional hypotheses E.g. ‘The more anxious someone is, the worse they will perform’ VERSUS ‘I am not sure how anxiety will affect performance’ Pearson’s r Pearson’s r can have a value between 1 (perfect positive correlation) and -1 (perfect negative correlation) Level of significance p <.05 p