unit 1
What is a Quantative variable?
Take number values for which it makes sense to find an average.
What is the Least-Squared Regression Line?
The linear model that minimizes the squares of the residuals.
What is a Sample?
When a portion of the population is left out when collecting data
Under coverage
Fill in the blank:
If the p is low, ______
Reject the Ho
What is a Categorical variable?
Assigns labels that place individuals into particular groups.
What is FODS?
Form
Outlier
Direction
Strength
What is the type of sampling where several different sampling methods are used in different stages.
Multistage Sampling
You can only make inferences on a ______
Controlled experiment
What is a Type I error
Type I Error: The null hypothesis is true, but we mistakenly reject it.
How do you find Low and High Outliers?
Low: < Q1 - 1.5 x IQR
High: > Q3 + 1.5 x IQR
What is a Weak and what is a Strong Correlation Coefficient (r).
Weak: 0 to 0.3
Strong: 0.8 to 1
What is it called when the subjects in an experiment do not know if they are in treatment or control.
Single Blind
What response bias - reviews entered on a website.
Type II Error: The null hypothesis is false, but we fail to reject it.
What are Conditional and Marginal distributions?
Conditional: Compares to a subgroup
Marginal: Compares to the entire group
What are the three Conditions for Correlation
1) Quantitative, Bivariate Data
2) Linear association
3) No outliers
A fake treatment given to the control group
Placebo
When a data set is multiplied by a number it changes ....
Mean and Standard Deviation
When do you use this formula:
Sqr root(p(1-p)/n)
Standard deviation
What is a Z score and what do positive and negative Z scores mean?
Number of standard deviations away from the mean a given score is. Positive is above the mean and negative is below the mean.
What is Extrapolation?
A statistical technique aimed at inferring the unknown from the known.
Data in the past is studied.
Retrospective study.
Any explanatory variable in an experiment.
A factor
What are the 5 steps for a confidence interval
1. State the Title
2. Assumptions Satisfied
3. Model with Parameters
4. Do the Math – State CI
5. Conclusion in context