math review

the simple random sample is

Bechhofer, Taylor, Weiss

In order to assess the opinion of students at the University of Minnesota on campus snow removal, a reporter for the student news paper interviews the first 12 students...

a convince sample

a simple random sample of size n is defined to be

a sample of size n chosen in such a way that every set of n units in the population has an EQUAL chance to be the sample actually selected

a lurking variable is

a. variable that is not among the variables studied but that affects the response variables

when controlled experiments are impractical or unethical, which of the following would be necessary to establish cause- and -effect relation between two variables?

all of the above

the intended population for this survey is

all residents of Lafayette

the essential different between an experiment and an observational study is that

an experiment imposes treatments on the subjects, but an observational study does not

which of the following statements about a randomized complete block design with two treatments is not true?

block a is chosen randomly from along the available experimental units

a stratified random sample addresses the same issues as which of the following experimental designs?

block design

which of the following is NOT a major principle of good design for all experiments?

blocking

a marine biologist wants to estimate the mean size of the barnacles semibalanus balnoides on a stretch of rocky shoreline

cluster sampling

to determine the promotion of each color of peanut butter M&, you buy 10 1.69 ounces packages and count how many there are of each color. Ex of?

cluster sampling

the principle reason for the use of random assignment in designing experiments is that it

creates approximately equal groups for comparison

the principle reason for the use of controls in designing experiments is that it

distinguishes a treatment effect from the effects of confounding variables

a double-blind experiment was conducted to evalure the effectiveness of the Salk polio vaccine. .... of the treatment status of the experimental subjects was to

eliminate a possible source of bias

the most important advantages of experiments over observational studies is that

experiments can give better evidence of causation

an experiment was conducted by some students to explore the nature of the relationship between a person's ♡ rate (measured in beats per minute)...♡ rate was then measured at the end of this period. The variables "stepping rate" and "step height" are the

factors

an experiments' compares the taste of a new spaghetti sauce with the taste of a commercially successful sauce readily available in grouchy stories. this is called?

matched pairs design

in order to select a sample of undergraduate students win the United States, I select a simple ransoms sample of four states. For each of these states, I select a simple random sample of two colleges or universities.

multisage sampling

an opinion research firm wants to find the country's reaction to a speech by a famous politician. they randomly select six states.....

multistage sampling

frequently, telephone poll-takers call near dinner time-between 6pm and 7pm - because most people are at home then. This is an effort to avoid?

nonresponse

the principle reason for replication in designing experiments is that it

reduces sampling varaivaility

in an experiment, an observed effect so large that it would rarely occur by chance is called

statistically significant

we divide the class into two groups:first year students and others. We then take random samples from each group, this is an example

stratified random sampling

the sample for the survey is

the 20 people who gave the sportswriter their opinion

a study of elementary school children, ages 6 to 11, finds a high positive correlation between shoe size x and score y on a test of reading comprehension. The observation correlation is most likely due to

the effect of lurking variable such as age

a marker research company wishes to find out whether the population of students at a university prefers brand A or brand B of instant coffee.

which brand they prefer

one hundred volunteers who suffer from sever depressions are available for a study. the factor of the study is

which treatment the volunteer receive