Awoman has a large garden and decides this year she will not let the pests get beyond control. at the earliest sign of insect pests, she applies an organic insecticide and continues to apply it every month throughout the growing season. the next year the woman decides not to use any insecticides, thinking that she must have eliminated the pests with the prior year's treatments. unfortunately, the pests reappear in numbers greater than she has ever seen before, and her crops are destroyed. investigating this phenomenon, she learns that she has just experienced a phenomenon known as:

Psychologists studying infant memory want to determine at what age babies can remember specific events. an experimenter uses several puppets to demonstrate a series of actions while the infant watches. after a delay, the experimenter records how many of the actions the child imitates when playing with the puppets. what is the dependent variable?

Asociologist wants to study a culture that occurs in some women’s prisons: “state families,” in which individual prisoners take on certain roles within a group of like-minded prisoners. there is previous evidence that younger prisoners will use older inmates who play the roles of grandparents as a resource before they will turn to staff for and advice. the lieutenant in charge of a dorm of long-term prisoners offers to gather volunteers to speak to the researcher and also offers to vouch for the integrity of the researcher. the use of this staff is: a valid use of a statistical technique referred to “snowball sampling” wherein the inclusion of the first subject leads to the recruitment of another one subject.a useful tactic in obtaining a sample of prisoners who both meet the criteria and who will be honest with the researcher.wrong and is prohibited; subject selection needs to be free from intervention by prison authorities or prisoners.acceptable only when the researcher’s irb grants a special waiver.

The american public was excited by the invention of the railroad system. true false