In a standard 52-card deck, where each card is assigned a numeric value, the mean of the 52 cards is 7.0 with a standard deviation of 3.742. To test if a representative sample can be attained, the deck is shuffled and 13 cards are randomly drawn, one at a time. Each card is recorded and then returned randomly to the deck before the next card is drawn. This process of drawing 13 random cards is repeated a total of 20 times, and the mean and standard deviation of each round is computed.
Which type of sampling is this an example of?
Randomization
Multiple comparison
Matched pairs
Bootstrap correct answerBootstrap
A study is done to determine if the color of an apple affects the purchase rate by consumers at a grocery store. Purchase counts for three colors of apples are collected.
Which technique should be used to determine if there is a difference in purchase rate by color?
Rank-based
Randomization
t-test
ANOVA correct answerANOVA
A hospital network collects the amount of time it takes doctors to see patients.
Which two techniques are appropriate to compare the mean times of two subsets within this set of doctors?
Choose 2 answers
ANOVA
t-test
Logistic regression
Principal component analysis correct answerANOVA
t-test
A data analyst needs to determine whether antioxidants in blackberries can reduce age-related cognitive decline. Twenty-five adults between 65 and 80 are selected to eat blackberries for six months and be retested. The original scores are compared with the second scores to determine whether there was decline.
What is the appropriate model to test the hypothesis?
z test
ANOVA
Linear regression
Two-sample t-test correct answerTwo-sample t-test
Which assumption does a data analyst have to make when performing ANOVA on a dataset?
There are just two parameters that are being estimated.
The error terms follow a normal probability distribution.
The parameters are additive.
The explanatory variable is continuous. correct answerThe error terms follow a normal probability distribution.
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