If no correlation exists between the variables, the points appear randomly scattered on the coordinate plane. If a large correlation exists, the points concentrate near a straight line. Scatter plots are useful data visualization tools for illustrating a trend. If the vertical (or y-axis) variable increases as the horizontal (or x-axis) variable increases, the correlation is positive.
Whiplash Whiplash, a severe neck injury, can cause stiffness and pain in the neck, headache, dizziness, and more. Aortic stenosis Aortic stenosis is a condition of the heart causing shortness of breath, dizziness, or chest pain.
The joints, discs, muscles, and ligaments of the neck all contain nerve endings which are sensitive to neck injury or strains that can result in headaches. The pain of neck related headaches is usually worse at the base of the skull, and may spread to the forehead, temples, eyes, face and shoulder.