Preeyam Roy IPAT model Definition: I = P ?A ?T ?S It?s a formula used to see how population affects the environment Sentence: in the IPAT model, P stands for population, a for affluence, t for technology, and I for total impact of environment technology Definition: Sentence: demography Definition: the application of population ecology to the study of change in human populations Sentence: demography helps us understand human reproduction and effects in communities and the environment Population density Definition: the number of individuals per unit area Sentence: Age structure Definition: relative number of organisms of each age and gender within a population Sentence: Age structure is also known as age distribution Sex ratios Definition: the proportion of males to females