Sports
a “fake” treatment that looks just like the treatment being tested
placebo
control, randomization, replication
3 principles of experimental design
include the individuals who are convenient for us to sample
convenience sampling
identifies a group of subjects and examines their past
retrospective sampling
obtained by selecting every kth individual from the population
systematic sample
smaller group of individuals selected from the population
sample
Subjects don’t know their treatment group
blind
Small group of individuals chosen from the population
double blind
Includes everyone and “samples” the entire population
Census
taking fake treatment causes response.
Placebo effect
the population is divided into strata and a random sample is taken from each stratum
stratified sample
Telephone surveys leave out people with no phone,
undercoverage
every possible combination of individuals has an equal chance to be selected
Simple Random Sample (SRS)
Sample subjects that are the easiest to do
Trial
identifies a group of subjects and then tracks them over a period of time
prospective study
Those who don’t respond may differ from those who do respond and they may differ on the variables
nonresponse bias
probability sampling technique in which clusters of participants within the population of interest are selected at random
cluster sampling
a large group of individuals is invited to respond and all who do respond are counted
voluntary response sample
Sampling methods that tend to over or under emphasize some characteristics of the population
Biased
2 random samples are selected, a random sample of clusters, then a random sample of people within those clusters
multistage sampling
A die is rolled until all faces appear at least once. Find the average number of tosses for this to happen. Use the Monte Carlo Method and 20 trials
.6
A coin is tossed until three heads are obtained. Find the average number of tosses necessary for all three heads to show up. Use the Monte Carlo Method to answer and do 30 trials
.3
Describe this experiment with a diagram. Researchers plan to investigate a new medication that may reduce the conditions of having a fever. 80 volunteers with a high fever are solicited. Volunteers are randomly assigned 100 mg of the medicine or a placebo.
group 1 ---- placebo
cluster- > compared fever conditions
group 2 ---- real medicine
when playing a game the number of spaces you move is determined by rolling the die. if you are 10 spaces away hoe many turns will it take it? run 20 trials, then calculate the average number of turns it took you to win.
.12
a science laboratory wants to examine the effects of a photosynthesis on plant growth. one row of plants gets the sun and the other row of pants doesnt get the sun for three months.
control group is the row of plants that dont receive the photosynthesis because the control group is the group that doesnt receive the treatment in an experiment