Application of Correlation

“The longer a person spends in direct sunlight, the severer the sunburn.” This is a correlation made by health experts which tries to explain that too much exposure to direct sunlight is harmful to the human body. There is a limit to which sunlight is useful to the body after which the harm it causes from this limit is directly proportional to the hours of exposure.  The effects of hours spent under direct sunlight are not there in the initial hours and therefore the gradient of a curve at this point is negative. Once the limit is reached, the immediate effects on sunburn are very small because the skin damages are temporal and easy to recover from.

More exposure in terms o the number of hours advances the effect whereby wrinkles and ageing of the skin is seen. The skin becomes darker and some colored pigments tend to appear on the skin. Extensive exposure now may lead to development of skin cancer because the ultra violet rays are able to penetrate deeper into the epidermis and absorbed. Skin cancer and other long-term effects of overexposure are the optimum results which are very hard to recover from.

From this correlation example, it is clear that the number of hours that one is exposed to direct sunlight after the useful limit is proportional to the sunburn effects. A graph of the sunburn effects against the hours of exposure would be a straight line that does not pass through the origin. This correlation could be applied to inform the people who work outdoors about the various risks that result from long hours of exposure to the direct sunlight.  

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