Probability
The probability of going on a walk and seeing no golden retrievers if the probability of seeing a golden retriever while on a walk is 0.12.
What is 0.88 or 88% percent?
We are 99% confident that the interval from 0.68 to 0.82 contains the true proportion of females that were at a college women's volleyball game.
What is the interpretation of an interval?
The manager of a large company that sells pet supplies online wants to increase sales by encouraging repeat purchases. The manager believes that if past customers are offered $10 off their next purchase, more than 40% of them will pace an order. To investigate the belief, 90 customers who placed an order in the past year are selected at random. Each of the selected customers is sent an e-mail with a coupon for $10 off the next purchase if the order is placed within 30 days. Of those who receive the coupon, 38 place an order. Is there convincing statistical evidence, at alpha 0.05 that the manager's belief is correct.
What is a 1 proportion z-test?
An survey asks the following question: How many siblings do you have.
What is a Quantitative variable?
A student would like to compare whether the new soil brand he purchases is more effective at growing his tomato plants than his current soil. A large tree sits in the corner of his backyard, shading half of his garden. To conduct his experiment, he separates the shady and sunny areas in his garden and splits each of those areas into six smaller areas. He randomly assigns three of the slots in his sunny area to contain his original soil while the other utilizes the new soil. He repeats the same process for the shady area.
What is a block design?
The probability of flipping a coin and it landing on heads for 5 flips in a row.
What is 0.03125 or 3.125%?
(0.5)5 = 0.03125
Assuming the probability of Mrs. Hancock's students passing the AP statistics exam is greater than 0.7 probability, there is a 0.00004 probability that you get a sample proportion of 0.8 or greater by chance.
What is the interpretation of p-value?
McDonald's has two shifts a day, a night shift and morning shift. Burgers produced by the two shifts must meet the same specifications. The manager believes there is a difference between the proportion of burgers produced with the specifications by the two shifts. To investigate this belief, random samples of burgers produced on each of these shifts were selected. For the day shift 180 out of 200 selected burgers met the specifications. For the night shift 188 out of 200 burgers selected met the specifications. Use a 96% confidence interval to estimate the difference in the proportions of burgers produced within the specifications by the two shifts.
What is a 2 proportion z interval?
An exit poll surveys voters on who they voted for on their ballot.
What is a categorical variable?
To determine what products are popular in the store, a cashier asks every fifth customer what items they most often purchase from the store.
What is a systematic random sample?
To get out of jail in Monopoly you have three tries to roll "doubles." Given that the chance of rolling doubles is 1/6, what is the probability that you will get out of jail in three tries (or fewer)
What is 0.423 or 42.3%?
geometriccdf (p=0.167, x=3)
The slope of the sample LSRL for absence and final grades typically varies from the slope of the population LSRL by about 1.2 points/absence.
What is the interpretation of standard error of the slope?
A manufacturer wanted to know if more coupons would be redeemed if they were mailed to the female in the household rather than the male in the household. A coupon book was sent at random to either the male or female of the pair. The manufacturer found that the mean difference (female-male) in the number of coupons redeemed was 1.5 with a standard deviation of 4.75. Using an alpha of 0.05, do these data provide condensing evidence that the mean number of coupons redeemed is greater when the coupons were addressed to a female?
What is a Paired t-test?
To determine which snacks to bring to her friend's birthday picnic, she asks her friends whether they enjoy sweet or savory snacks.
What is a categorical variable?
To determine whether a student's seating placement impacts their performance in class, a teacher conducts an experiment. She begins with assigning each desk in the classroom a number of 1-32. Next she writes each of her 29 students name of equally sized slips of paper and places each into a hat and shakes it up. Starting with seat 1, she pulls out a student's name and assigns them to this seat. She repeats this process for each of the 29 students.
What is a completely randomized design?
The probability of walking into a dealership and seeing at least 3 purple cars in a dealership that has 52 cars if the probability is seeing a purple car in a dealership is 0.03 or 3%.
What is 0.205 or 20.5%?
Binomial dist (n=52,p=.03,x=2) = 0.795
1-0.795
Binomial (either seeing or not seeing a purple car)
Independent
Fixed number: 52 cars
Same probability: 0.03
75% of high school student's SAT scores are less than or equal to 1200.
What is the interpretation of percentile?
Skittles states that all colors of skittles are evenly distributed: red, orange, yellow, purple, green. However Phil thinks that the distribution of skittles is not equal. In a random sample of 100 skittles there were 10 green, 40 red, 10, yellow, 15 orange, 25 purple. Is there convincing evidence that the state's distribution of skittle colors is not true?
What is X² GOF test?
A teacher asks students how often they studied for their most recent exam.
What is a quantitative variable?
To determine if the meal selection offered by the company impacts whether or not employees eat lunch there a manager separates employees by their meal preferences (vegetarian, vegan, gluten free, and eats meat) and randomly selects 5 employees with each dietary preference to survey. The manager asks the following two questions:Do you feel satisfied with the meal selection offered by the company? and How often do you eat company offered meals in a week.
What is a stratified random sample?
Two PE classes recently ran a mile. The mean time PE class took to run a mile is 8.22 minutes with a standard deviation of 1.11 minutes. The mean time PE class B took to run a mile is 7.8 minutes with a standard deviation of 1.27 minutes. Let T equal the difference in miles times for PE class A and PE class B. What if the standard deviation of T.
What is 1.69 minutes?
square root 1.112+1.272 = 1.69
If the true mean temperature in California is 68 degrees F, there is a 0.75 probability the significance test will correctly reject a null hypothesis of population mean = 70 degrees F.
What is the interpretation of power?
Your ears and nose grow throughout your whole life. To quantify the expansion of ears over time a random sample of 30 adults were selected. For each adult, their age (in years) was recorded and their ear height (cm) was measured. Below is the regression output. Is there convincing evidence of a positive linear relationship between age and ear height?
What is 1-Sample t-test for slope?
A student is collecting data for a school project. He asks his peers how much sleep they got last night.
What is a quitiative variable?
To assess sales revenue for a chain department store, they randomly select 10 flagship stores and record each of the 10 store's revenue for each month within the last year.
What is a cluster sample?