Basics
Graphs
Experiments
Sampling
Misconceptions
100
What are the measures of center?
Median and Mode
100
What graph is best used for a quantitative variable?
Histogram
100
What are the types of experimental design?
Completely Random, Block Design, and Matched Pairs
100
What is a sample?
Group of cases with recorded information
100
Disjoint and indpendent events are the same.
False! Independent mean outcome of oen trial does not infleunce the outcome of any other trial. WHile disjoint means they cannot happen at the same time.
200
What parameters are resistant to outliers?
Median and IQR
200
What graph is best used for a categorical variable?
Bar Graph
200
How many cases are there?
6
200
What are the types of biased sampling?
Voluntary, convenience, undercoverage, non response, response bias, poor questionnaire design
200
Are stratified random sampling and block design the same?
No, stratified random sampling is used for SAMPLING while block design is used for experiments.
300
When a single outcome is substantially different from some pattern that the rest of the data follows.
Outlier
300
What is the total area under a density curve?
1
300
You decide to play the lottery. While it is possible to win the lottery, nobody that you know has won the lottery before. Is this a random experiment or not?
Yes, it is indepedent because knowing someone who has won the lottery does not increase yoru chance of winning.
300
What is the difference between sampling frame and sampling design?
Sampling frame = List of all possible cases in a population
Sampling Design = methof used to select sample from population
300
Is it necessary to remove all outliers when calculating data?
No, just if it is an influential case
400
How do you find the median?
(n+1)/2
400
What must a normal distribution be?
Symmetric, single-peaked, and bell shaped
400
What is the difference between r and r2?
r = the correlation coefficient and tells us aout strength and direction IF linear
r2 = coefficient of determination and tells us about teh strength of a linear relationship. It is the only way to make an interpretation of the realtionship.
400
What is the type of sampling that each fixed subset has the same chance of selection?
Simple Random Sample
400
Is the z-score the same as the probability of an event?
No, it is just how far a way a value is from the mean. Use z-score to find the probability.
500
Why do we use z-score?
To be able to calculate the probability of a certain event, and compare data sets
500
What is the Empirical Rule.
68% within 1 st.dev. of the mean
95% within 2 st.dev. of the mean
99.7% within 3 st.dev. of the mean
500
A group of Olympic Athletes tracks the number of calories they eat each day over a two-week period. On some of these days, they compete, and on some days they don’t compete.
Observational Study
500
You decide to conduct an experiment using the UVA student population. You survey 100 students. Who is the population?
UVA students
500
r=0 means there is no correlation
False. It means that there is no linear realtionship, there could still a very strong correlation.