Probability, Random Variables, and Probability Distributions
If the probability that an individual randomly selected from a population prefers brand A over brand B is 0.3, and you select 150 individuals at random, which of the following is the approximate standard deviation of the number of individuals who prefer brand A?
If the probability of success on a single trial in a binomial experiment is 0.2 and we want to find the probability of exactly three successes in ten trials, which calculation is appropriate?
10^3(0.2)^3(0.8)^7
(0.2+0.8)^{10}
If you were told that only six out of twenty sampled marbles drawn at random are blue and assuming these draws represent Bernoulli trials, what information would you still require to determine if this forms part of data appropriately modeled by the binomial distribution?
The exact shade variation among blue marbles
The total count of marbles present at beginning
Whether or not each marble was replaced after drawing it
Whether or not more colors than blue exist within sample space
When increasing the number of trials in a binomial experiment, what is the effect on the shape of the distribution if p remains constant?
The distribution becomes skewed to the left.
There's no change to the shape of the distribution.
The distribution becomes more symmetric.
The distribution becomes skewed to the right.
What is the maximum likelihood estimator (MLE) for the parameter p in a binomial distribution where k=800 successes were observed over 4000 trials?
0.20
0.75
0.50
0.10
How is cluster-sampling different than stratified-sampling?
Cluster-sampling is based on characteristic of interest, whereas stratified-sampling is systematically selected.
In cluster-sampling, selected individuals outside of predetermined clusters, whereas stratified-sampling uses all possible groups.
In cluster-sampling, randomly selected groups or clusters, whereas in stratified-sampling, selects randomly within specific groups or strata.
Which term describes the probability of success on an individual trial in a binomial distribution?
q
n
k
p

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When flipping a fair coin three times, what parameter represents the expected number of tails?
How does increasing only the probability of success ('p') while keeping the number of trials ('n') constant affect the standard deviation of a binomial distribution?
The standard deviation will increase due to higher probability of successes.
There is no set pattern; it depends on other variables in the experiment.
The standard deviation will decrease because the formula is .
Standard deviation remains unchanged since the number of trials is constant.
What is the probability of success in a binomial distribution called?
k
n
p
q