Section 1.1 - Introduction to the Practice of Statistics

1. Explain the difference between a population and a sample.
A population is the entire group to be studied and a sample is a portion of the population.

2. Explain the difference between a parameter and a statistic.
A statistic is a numerical summary of a sample and a parameter is a numerical summary of a population.

3. What is Descriptive Statistics and how is it used?
Descriptive statistics describes the results of a sample without making conclusions of the population.

4. What is Inferential Statistics and how is it used?
Inferential statistics uses the result of a sample to apply to a population.

5. Determine whether the following variables are qualitative or
Once the treatments were complete, it was determined that 85% of the patients in Group 1 and 60% of the patients in Group 2 had complete resolution (removal) of their warts. The researchers concluded that duct tape is significantly more effective in treating warts than cryotherapy.

a) What is the research objective?
To determine if the use of duct tape is as effective as the use of cryotherapy for the removal of warts.

b) What is the population being studied?
People who have warts

c) What is the sample?
The patients in the two groups

d) What are the descriptive statistics?
85% of patients in group 1 and 60% of patients in group 2 had complete removal of their warts.

e) What are the conclusions of the study?
Duct tape treatment is more effective than cryotherapy for the removal of warts. Section 1.2 - Observational Studies Versus Designed Experiments

14. What is an explanatory variable?
An explanatory variable is the variable which is used to explain the outcome of another variable in a study.

15. What is a response variable?
A response variable is the variable in a study that is affected by an explanatory variable.

16. What is meant by confounding factors in a study?
Confounding factors in a study refers to other variables that may cause an outcome of a study.

17. What is a lurking variable? Give an example of a lurking variable.
A