Introduction. The standard deviation is a measure of the spread of scores within a set of data. Usually, we are interested in the standard deviation of a population. However, as we are often presented with data from a sample only, we can estimate the population standard deviation from a sample standard deviation.ntroduction. The standard deviation is a measure of the spread of scores within a set of data. Usually, we are interested in the standard deviation of a population. However, as we are often presented with data from a sample only, we can estimate the population standard deviation from a sample standard deviation.
Itching usually results from dry skin, a skin disorder, or an allergic reaction. If the person has no rash or skin abnormalities, the cause may be a drug, an allergic reaction that has internal effects, or a systemic disorder.
This causes your skin to become dry and irritated. You may first notice this around the T-zone of your face although it can spread over your whole body. Raised stress levels can exacerbate itching as stress triggers the release of histamine, which can cause flushing, itching and sometimes skin rashes. As many mid-life women are dealing with stressful circumstances, working to support and calm the nervous system is important.