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.
Response to Intervention. Response to Intervention (RtI) is an approach that schools use to help all students, including struggling learners. The RtI approach gives Texas students opportunities to learn and work at their grade level. The idea is to help all students be successful.esponse to Intervention. Response to Intervention (RtI) is an approach that schools use to help all students, including struggling learners. The RtI approach gives Texas students opportunities to learn and work at their grade level. The idea is to help all students be successful.