Vocabulary
Z-score
Probability
Confidence Interval
Tests of Significance
100
Inference
What is the process of drawing conclusions about a population on the basis of sample data
100
The percentage of data greater than a z-score of 2.4?
What is 0.82%
100
Consider the table below, which describes the probability that a randomly-selected dorm room has the given number of beds.
Give the probability of a dorm room having 3 or more beds.
What is 0.507?
100
The formula for the margin of error
What is z*(σ/sqrt(n))?
100
You have a z-score of 2.5 and your alpha level is 0.01, can you reject the null hypothesis if it is a two-tailed test?
No, p=0.0124 which is greater than 0.01
200
A numerical characteristic of a population, such as the population mean or population standard deviation
What is a parameter?
200
Suppose that blood sugar levels are normally distributed with a mean of 100 mg/dl (milligrams per deciliter) and a standard deviation of 10mg/dl. David has a blood sugar level of 85 mg/dl. Calculate David's z-score.
What is z=-1.5
200
The number of blue marbles in a bag if 20% of the marbles are red, 5% are white, 30% are green, 15% are black, and the rest are blue. There are 40 marbles total
What is 12 marbles
200
The upper limit of a 90% confidence interval of the trunk length of elephants if a study of 100 elephants has a sample mean of x̄=7ft with a standard deviation of σ=1ft
What is 7.1645
200
Test scores are normally distributed with a mean of 85% and a standard deviation of 5.4%. You believe people who went to tutoring did significantly better. There are 100 kids who went to tutoring and their mean score was 89.7%. Write out the null and alternative hypotheses.
Ho: µ=85 Ha: µ>85
300
Sample Space of a random phenomenon
What is the set of all possible outcomes
300
The maximum weight a pumpkin can be and still be in the lower 16% of the weight of all pumpkins if the weight of pumpkins is normally distributed with μ=100 and σ=25lb.
What is 75lb?
300
Draw that sample space for a coin flipped 4 times.
300
The sample size that gives a margin of error of at least 1.2 for a study of the weights of narwhals that has a sample mean of x̄=1200 and a standard deviation of σ=40lbs with a confidence level of 99%
What is 7374 narwhals?
300
The time it takes to download a video game is normally distributed with µ=2 hrs and σ=1hr. Dave believes it takes longer than 2 hrs to download a video game and so he randomly downloads 20 video games and finds the average time it takes to download a video game to be 2 hours and 30 minutes. What is the null hypothesis, alternative hypothesis, P-value, and statistical significance of the P-value at a significance level of α=.01
Ho: µ=2hrs, Ha: µ>2hrs, P=.0127, Not statistically significant and can not reject null hypothesis
400
Assigns probabilities as areas under a density curve
What is a continuous probability model?
400
Weights of babies are approximately normal with μ = 7.7 pounds and σ = 1.1 pounds, N(7.7, 1.1). What weight would put a newborn baby in the 95th percentile?
What is 9.51 pounds?
400
What is 20%?
400
The margin of error for a 90% confidence interval where the mean is 5.4, the standard deviation is 1.1, and the sample is 16 individuals
What is 0.452?
400
You run an experiment to see if your sample is significantly shorter than the US population. Your sample has a mean height of 65.9in. The population has a mean height of 67.1in and a standard deviation of 2.1in. Is your sample significantly shorter at the 0.05 level? (n=16)
Yes, p=0.0111 therefore it is statistically significant
500
The independent variable of an experiment is also called
What is the explanatory variable?
500
One year, many college-bound high school seniors in the U.S. took the Scholastic Aptitude Test (SAT). For the verbal portion of this test, the mean was 425 and the standard deviation was 110. Based on this information what percentage of students would be expected to score between 350 and 550?
What is 62.45%
500
The probability of rolling two 6 sided die and getting sums of 2, 3, 7, and 10
What is .33?
500
The approximate sample size of a study of the time it takes hippos to walk up a hill if there is a 95% confidence interval of 7 minutes to 10 minutes with a standard deviation of σ=500 seconds
What is 119 hippos?