170717P - PRINCIPLES OF EPIDEMIOLOGY HEALTH RESEARCH COURSE: SIX PROPERTIES OF RVS AS A BASIS FOR DESCRIPTIVE STATISTICS

Presentation at a Course on Principles of Epidemiology, Health Research Faculty of Medicine, King Fahad Medical City, October 11-12, 2017 by Professor Omar Hasan Kasule Sr. MB ChB (MUK). MPH (Harvard), DrPH (Harvard) Chairman of the Institutional Review Board / Research Ethics Committee at King Fahad Medical City, Riyadh.

LECTURE # 4: SIX PROPERTIES OF RVS AS A BASIS FOR DESCRIPTIVE STATISTICS

THE 6 PROPERTIES

1. EXPECTATION: The expectation of a random variable is a central value around which it hovers most of the time. 
2. VARIANCE: The variation of the random variable around the expectation is measured by its variance.
3. COVARIANCE: Covariance measures the covariability of the two random variables.
4. CORRELATION: Correlation measures the linear relation between two random variables.
5. SKEWNESS: Skewness measures the bias of the distribution of the random variable from the center. 
6. KURTOSIS: Kurtosis measures the peakedness of the random variable at the point of its expectation 

NORMAL DISTRIBUTION SHOWING EXPECTATION:

 

NORMAL DISTRIBUTION SHOWING VARIANCE:

SCATTER PLOT SHOWING CORRELATION:

DISTRIBUTION SHOWING POSITIVE & NEGATIVE SKEW:

DISTRIBUTION SHOWING KURTOSIS: