Sample Statistics. 1  x refers to a sample mean. 2  s refers to the standard deviation of a sample. 3  s2 refers to the variance of a sample. 4  p refers to the proportion of sample elements that have a particular attribute. 5  q refers to the proportion of sample elements that do not have a particular attribute, so q = 1 - p.
Ecology/Environmental Response. The most basic interest of ecologists is how organisms interact with their environment. Inanimate objects do not normally interactâthey are simply acted upon by forces in the environment. Organisms, however, cannot be totally passive within a chain of events and still sustain life.
Our environment is constantly changing, and in order for us and other living things to survive those changes, we must be able to respond to them. Any detectable change in the environment is called a stimulus. Usually, a stimulus is a product of change in an energy source or force, such as light, or sound, or heat. As humans, we detect and respond to stimulus in order to survive.