In Exercises 5–20, assume that the two samples are independent simple random samples selected from
19. Is Old Faithful Not Quite So Faithful? Listed below are time intervals (min) between eruptions of the Old Faithful geyser. The “recent” times are within the past few years, and the “past” times are from 1995. Does it appear that the mean time interval has changed? Is the conclusion affected by whether the significance level is 0.05 or 0.01?
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ELEMENTARY STATS. 18 WEEK ACCESS CODE
- , 16. A statistically minded fraternity junior keeps records on how many girls he has to ask before one agrees to be his date for a Saturday football game. His school plays five home games and his five acceptances come on the 3rd, 6th, 4th, 2nd, and 9th girl he asks. Assume that the probability, e, that any girl he asks will accept his invitation is constant from girl to girl. Mind ML estimate of e.arrow_forwardStock A has an expected return of 10% and standar deviation of 20%. Stock B has an expected return of 15% and standard deviation of 25%. The minimum variance portfolio (MVP) consisting of Stocks A and B has an expected return of 12% and a standard deviation of 5%. The risk-free rate equals 3%. The correlation between Stocks A and B equals________ A) +1B) –1C) Less than +1 and greater than –1D) Cannot determine without more dataarrow_forwardResearchers claim that the surface temperature of the world's oceans mainly changes with changing latitude. The warmest waters are near the equator and the coldest waters are in the Arctic and Antarctic regions. To examine this claim, an experiment has been designed and the following data has been collected from coastal areas in the southern hemisphere for 5 consecutive years in the middle of November. The recorded temperatures are all averages across the 5 years of data. Coastal ocean Surface Temperature Latitude TERENGGANGG 44 42 40 38 36 34 32 30 28 26 24 22 20 18 16 14 12 10 8 6 14.1 15.2 16.2 17.5 18 21 22.1 23.8 24.5 24.2 24.4 26 26.9 28.2 28.5 28.8 29.8 29.8 31.2 32.5 Coastal Air Temperature 16 17 15 15 18.5 22 24.5 24 25 26.5 30 31.6 30.4 33.5 33 32 32 33.5 34 30 Note: Temperature.xlsx is also attached. a) Convert the latitude numerical variable to a categorical variable with 4 levels (very low, low, moderate, high), using a statistical software package. Find the overall mean,…arrow_forward
- The probability that a Poisson variate x takes a positive value is (1 – e-1.5). Find the variance and also the probability that x lies between –1.5 and 1.5.arrow_forward13. Answer the following for the probability distribution 1 f(x) = (2x + 1) (2x + 1) X= 0, 1, 2, 3 16 a. Find the mean and the variance. μ = b. EX²-4X+6) 0²=arrow_forwardCan you please help me with part D, thank youarrow_forward
- Suppose that a small company purchases 300 of these 75-watt LEDs with a guarantee that 97% of them will last for more than 25,000 hours. Assuming the guarantee is correct, what is the expected number of them that will last for more than 25,000 hours? 0 O 270 288 291 O 280 USE THE INFORMATION BELOW TO ANSWER QUESTIONS 24 THRU 27 Researchers are interested in possible relationships between smoking and cancer. The following two-way table shows the results of data taken for a total of 2500 randomly sampled adults (smokers who are 60 years old or older) who are categorized as Heavy Smoker, Moderate Smoker or Light Smoker, where the three types of cancers 23 www ACarrow_forwardThe mean of the time it takes for a product to arrive from China is 50 days and the standard deviation is 12 days. What is the probability that if 2 products are ordered from China, each of them will take 70 or more days to arrive. Assume that the arrival time of these 2 products are independent. Question 10 options: 0.00228 0.224 0.1225 0.0035arrow_forwardAccording to a 2006 survey conducted by the Center for Disease Control and Prevention (CDC), birth rates peak slightly between July and October each year. While a slight numerical increase in birth rates is often observed, this difference is assumed to be statistically non-significant. Thus, we would expect to see an equal number of people born during each month of the year in the United States. The "Birth Data.jasp" contains the birth months for 1380 babies (N = 1380) born during the year 2006 in the United States collected by the CDC. Conduct a Chi-Square Goodness of Fit Test at α = 0.05, to see if the number of babies born each month “fits” with the CDC’s assumptions about the population. Identify the correct value for df. A. 5.72 B. 11 C. 107 D. 0.89arrow_forward
- According to a 2006 survey conducted by the Center for Disease Control and Prevention (CDC), birth rates peak slightly between July and October each year. While a slight numerical increase in birth rates is often observed, this difference is assumed to be statistically non-significant. Thus, we would expect to see an equal number of people born during each month of the year in the United States. The "Birth Data.jasp" contains the birth months for 1380 babies (N = 1380) born during the year 2006 in the United States collected by the CDC. Conduct a Chi-Square Goodness of Fit Test at α = 0.05, to see if the number of babies born each month “fits” with the CDC’s assumptions about the population. Identify the correct null hypothesis. A. H0: The number of babies born throughout the year is equal across all 12 months B. H0: The number of babies born during the summer months is greater than the number of babies born during the rest of the year C. HA: The number of babies born in…arrow_forwardAccording to a 2006 survey conducted by the Center for Disease Control and Prevention (CDC), birth rates peak slightly between July and October each year. While a slight numerical increase in birth rates is often observed, this difference is assumed to be statistically non-significant. Thus, we would expect to see an equal number of people born during each month of the year in the United States. The "Birth Data.jasp" contains the birth months for 1380 babies (N = 1380) born during the year 2006 in the United States collected by the CDC. Conduct a Chi-Square Goodness of Fit Test at α = 0.05, to see if the number of babies born each month “fits” with the CDC’s assumptions about the population. What is the value of X2-crit? A. 5.72 B. 4.72 C. 19.68 D. 21.92arrow_forwardAccording to a 2006 survey conducted by the Center for Disease Control and Prevention (CDC), birth rates peak slightly between July and October each year. While a slight numerical increase in birth rates is often observed, this difference is assumed to be statistically non-significant. Thus, we would expect to see an equal number of people born during each month of the year in the United States. The "Birth Data.jasp" contains the birth months for 1380 babies (N = 1380) born during the year 2006 in the United States collected by the CDC. Conduct a Chi-Square Goodness of Fit Test at α = 0.05, to see if the number of babies born each month “fits” with the CDC’s assumptions about the population. Identify the correct alternative hypothesis A. H0: The number of babies born throughout the year is equal across all 12 months B. HA: The number of babies born in at least one month of the sample is equal to the number of babies born in at least one month of the population C. HA: The…arrow_forward
- Glencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw Hill