Vocabulary
68-95-99.7 Rule
Probability
Z Confidence
Interval
Interval
About Me
Significance
Test
Test
100
Observations that are significantly different from other observations in a data set and may skew the results of statistical analysis
What are outliers?
100
The length of a squirrel tail that is 3 standard deviations above the mean if the length of squirrel tails is normally distributed with μ=9in and σ=1.5in
What is 13.5in?
100
The percent of marbles in a bag that are blue if 20% of the marbles are red, 5% are white, 30% are green, and 15% are black
What is 30%
100
The formula for a z confidence interval
What is x̄±z*(σ/sqrt(n))
100
My name
What is Anne
100
The type of error if an innocent person is found guilty when the null hypothesis is that someone is innocent and the alternative hypothesis is that someone is guilty
What is a type I error
200
A variable that uses numbers and can be measured, but only has whole number values (ex. number of koalas)
What is a discrete variable?
200
The percent of the data that lies between 60lbs and 90lbs if the weight of dogs is normally distributed with μ=75lb and σ=15lb
What is 68%?
200
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?
200
The formula for the margin of error
What is z*(σ/sqrt(n))?
200
My favorite color
what is green?
200
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
300
A numerical characteristic of a population, such as the population mean or population standard deviation.
What is a parameter?
300
The percent of the data between the 3rd and 2nd standard deviations if the startup time of computers is normally distributed with μ=1min and σ=15s
What is 4.7%
300
Consider the table below, which describes the probability that a randomly-selected dorm room has the given number of beds.
Now consider a sample of 15 randomly-selected dorm rooms, with sample mean X beds.
Assume that the standard deviation of number of beds in all dorm rooms is 0.4 and the mean number is 2.3.
What is the probability of X ≥ 2.1?
What is 0.974?
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
My major
What is Economics?
300
A study is done that determines the length of geckos to be normally distributed with µ=7in Amanda believes the mean length of geckos is less than 7in and conducts her own study where she randomly measures 10 geckos and finds their mean length to be 6 inches and sample standard deviation to be s=1in. She conducts her study using a confidence level of 95% What is the null hypothesis, alternative hypothesis, P-value, and statistical significance of the P-value at a significance level of α=.05.
Ho: µ=7in, Ha: µ<7in, P=.00575, Statistically significant and reject null hypothesis
400
The type of study described: You (a researcher) are doing a study to determine if taking vitamin D supplements improves mental health. You have 100 participants in your study who are split into two groups. One group will get vitamin D supplements and one will get placebos. The participants do not know what group they are placed into and neither do you.
What is a double-blind experiment?
400
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?
400
The probability of rolling two 6 sided die and getting sums of 2, 3, 7, and 10.
What is .33?
400
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 7.1645ft?
400
A quirky fact about me
What is my grandfather went to school with Chuck Norris
400
A company claims that the average delivery time for its standard shipping service is 3 days. You suspect that the actual average delivery time is different. You randomly select 25 orders and record their delivery times. The sample mean delivery time is 3.5 days, and the sample standard deviation is 1.2 days. Conduct a one-sample t-test at a 5% level of significance to determine if there is evidence to support your suspicion.
Statistically Significant, Reject Null Hypothesis, t≈2.08 >t*95
500
The type of bias in this scenario: You (a researcher) send out a voluntary survey to all UO undergraduate students (~18,500) asking about their feelings on recent political occurrences, but you only get responses from students in politics clubs (800).
What is nonresponse bias?
500
The percent of data that falls beyond 3 standard deviations away from the mean plus the percent of data that falls between 5'10" and 6'3" if the height of all people is normally distributed with μ=5'5 and σ=5in
What is 13.8%?
500
The probability that a randomly selected person listens to 11 hours to 16 hours of music or 2 hours to 4 hours of music if the amount of time people spend listening to music every week is normally distributed with µ=10hrs and σ=3hrs.
What is .3656?
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?
500
What's a good meeting idea for Women in Economics Club
?
500
A manufacturer claims that the mean weight of a cereal box is 500 grams. To test this claim, a random sample of 40 cereal boxes is selected, and their weights are recorded. The sample has a mean weight of 495 grams and a standard deviation of 15 grams. Test at a 1% level of significance to determine if there is enough evidence to dispute the manufacturer's claim.
z≈−2.42 p=0.0155 not significant