Stats 355

Using graphs and numbers to describe data

based on haphazardly selectred individual cases

data thats collected for a particular purpose but can also serve as the basis for drawing sound conclusions about other research questions

Observeations of individuals and measure variables of interest but do not attempt to influence the responses

Deliberately impose some treatment on individuals and observe their responses

Individuals on which the experiment is done are the:

When the experimental units are human beings they are called:

When a specific experimental condition is applied to the units its called:

The explanatory variables in an experiment are often called:

The group of patients who receive a sham treatment is called:

if the design of a study systematically favors certain outcomes

The design of an experiment:

An observed effect so large that it would rarely occur by chance is called:

neither subjects themselves nor the medical personnel who worked with them knew which treament any subject had recieved

compares just two treatments by matching subjects in pairs

a group of experimental units or subjects that are known before the experiment to be similar in some way that is expected to affect the response to the treatment

The random assignment of units to treatments is carried out separately within each block

The basic principles of statistical design:

whats a tool for randomization?

What reduces the role of chance variation and makes the experiment more sensitive to differences among the treatments

The entire group of individuals that we want information about is called:

part of the population that we actually examine inorder to gather information

consists of people who choose themselves by responding to a general appeal

size n consits of n individuals from the population chosen in such a way that every set of