Types of Bias
This type of bias is present if the sampling method does not cover all groups of individuals in the population.
What is undercoverage bias?
In this most basic sampling technique, all possible individuals have the same chance on being selected.
What is a Simple Random Sample (SRS)?
The part of an experiment that the researcher actively changes about the subjects.
What is the treatment, factors, or explanatory variable?
In an experiment, this is necessary in order to draw a conclusion that generalizes to the whole population.
What is choosing a random sample?
A sample is said to be this if it (on average) over-estimates or under-estimates the proportion/percent of interest.
What is biased?
This bias occurs when sampling units are unreachable or do not answer a survey.
What is nonresponse bias?
Also referred to as a "counting-off" strategy of sampling, this method puts every nth individual in the sample.
What is a Systematic Random Sample?
The specific outcome measured at the end of an experiment.
What is the response variable?
This is necessary in experimental design in order to draw a cause-and-effect conclusion.
What is Random Assignment?
This is what we can conclude about two variables in an observational study or survey.
What is Association?
"Would you go against the Second Amendment and support the harsher regulation of firearms?" is an example of this type of bias.
What is response bias?
An example of this technique would be to randomly select a sample of Freshmen, Sophomores, Juniors, and Seniors while studying the satisfaction BHS students have with their guidance counselors.
What is a Stratified Random Sample?
Not an experiment because there are no applied treatments, but this can still be used to collect data on characteristics of interest in a sample and analyze the results for correlation.
What is an observational study?
This experimental design ensures that no one involved knows who got which treatment.
What is a Double-Blind study?
If you are recruited to participate in a taste test experiment, you would be acting as this.
What is an experimental unit?
This type of sampling method is a strategy for eliminating bias.
What is simple random sample?
While studying the proportions of colors of M&M's, you randomly select one bag, then survey all of the M&M's in this one bag.
What is a Cluster Sample?
An experiment is run to measure weight loss in which the treatment group is given a specific diet and exercise routine, while the control group is to eat and exercise as they usually do. Sleep and health conditions would be examples of these in this experiment.
What are confounding variables?
These are what needs controlled in an experimental design.
What are confounding variables?
This is what occurs when experimental units in a medicine experiment are told that they are being given a treatment that is supposed to have certain effects.
What is the Placebo Effect?
This type of bias occurred when the school principal asked a random sample of students if they did their homework last night and used the results to decide what proportion of students in the school did their homework.
What is response bias?
This sampling method produces high variability and constructs the sample by selecting individuals that are easily available.
What is Convenience Sampling?
The fake treatment in an experiment.
What is placebo?
This is a principle of experimental design that states there must be several experimental units.
What is Replication?
After an experiment, the results are compared to many other similar experimental results, and if the results stand out enough, then they are classified as this.
What is Statistically Significant?