Exam 1 Answers and Questions Define Psychology, Being sure to include the three general subjects we study? Psychology is the scientific study of affect, behavior, and cognition Explain each of the three words in the definition of empiricism? Empiricism is objectively quantifiable observation Objectively meaning other scientists and peers are agreed on the methods conducting the finding and that it can be reproduced for self-correction. Quantifiable meaning that we can measure what we are studying Observation meaning we can see the phenomena we are studying. Name and explain the three general principles of science that were discussed in class? Psychology doesn’t accept authority; it only accepts studies that have been proven to predict behavior. The findings must be tested and confirmed by a jury of peers. And that science is self correcting, so the study can be recreated. What are the two defining characteristics of a sample that were discussed in class? A sample is a sub set of a population and can be observed and measured. What is the difference between statistic and parameter? Statistics are descriptive number of a sample Parameter are descriptive numbers of a population Define sampling error? Sampling error is the differences between a sample statistic and its corresponding population parameter. What are the two implications of sampling error? Don’t expect your sample statistic to be a perfect representation of the population parameter. Two samples from the same population will yield slight different findings. What are the two things a researcher can do it minimize sampling error? The two things a researcher can do is increase his sample size, the larger the sample size, the less sampling error. And Random selection, to ensure that everybody has the same chance of being in the sample, how we make the sample representative of the population What can a researcher do to eliminate sampling error We can not eliminate sampling error, only reduce it. What is the two-step definition of research we discussed in class. Identifying a relationship between two variables and explaining that relationship with a theory-tested experiment to conclude cause-and-effect. What is the difference between a theory and a hypothesis? A theory is a proposed general relationship between an independent variable and a dependent variable. A hypothesis is a proposed specific relationship between the IV’s experimental manipulation and the DV’s operational definition. Write Independent variable (IV), Dependent Variable (DV), or Extraneous variable (EV) Variable that the researcher her must keep constant for all subjects: EV Variable that is used as the basis for creating the different experiment group: IV Variable that is measured by the researcher to see differences between the groups: DV Variable that is manipulated by the researcher: IV Variable that could affect the results but the researcher doesn’t want it to: EV Variable that is thought to be the “Cause” in cause and effect: IV Variable that is thought to be the “Effect” in cause and effect: DV What are the two defining qualities of an experiment? The researcher is able to manipulate the IV Tests are done under controlled conditions to factor out extraneous variables. Name and describe the two basic groups that are compared in an experiment? The two groups are the experimental group and the control group. The experiment group is the one that receives the experimental manipulation and the control group does not. What is the goal of random selection The goal of random selection is to make the sample representative of the population, it wants to reduce sampling error What is the goal of random assignment The goal of random assignment is to figure out which group is control and which group is manipulated. How is a quasi-experiment different from a normal experiment? A quasi-experiment can not manipulate the independent variable, such as age, gender, and race. Whereas an experiment is able to manipulate the independent variable. When we calculate correlation, what question are we trying to answer? The extent to which the two variables are related, whether positively or negatively When is it not necessary to use inferential statistics? It is not necessary to use inferential statistics when we can measure everybody in the population and do not need to take a sample. When testing a theory, we compare groups that have different amount of the Independent variable? How do we know if the theory is correct? The theory is correct when different amounts of the IV correspond to different amounts of the DV What is the difference between a discrete variable and continuous variable? Which one involves how mu8ch of a variable we have? A discrete variable is one that uses a nominal or ordinal scale and gives qualitative measures. A continuous variable gives intervals and ratios and gives quantitative measures with an absolute 0 measure; continuous variables involves measuring how much.