Planning a Study
the primary purpose of a study in statistics?
what is to answer a specific question or solve a problem.
The role of the control group in an experiment
What is to provide a baseline for comparison against the treatment group
A simple random sample
What is SRS, a sample where every group of a given size has an equal chance of being chosen
What is the influence on validity and reliability of conclusions drawn about a population
Statistical inference allows researchers to
The difference between a population and a sample
What is a population that includes all items of interest, while a sample is a subset of the population
Random assignment helps to achieve this
What is to balance of the effects of uncontrolled variables across treatment groups
Stratified random sampling
What is a method where the population is divided into strata based on shared characteristics, and an SRS is taken from each stratum
Voluntary response bias
What is bias that occurs when a sample consists entirely of volunteers, which may not be representative of that population
Statistically significant
What is a result unlikely to have occurred by chance/suggests a real effect
A sample survey
What is a type of observational study that uses a sample to learn about the population
Confounding variables
What is a variable that influences both the explanatory and the response variable, potentially leading to false association
Cluster sampling
What is a method where the population is divided into clusters, and entire clusters are randomly selected for data collection
Undercoverage bias
What is bias that arises from problems in the data gathering instrument or process (ex. leading questions, double-barreled statements, etc.)
Having a control group in terms of inference testing
What is allows researchers to determine whether effects observed in the treatment group are due to the treatment or other factors