The U.S. Geological Survey compiled historical data about Old Faithful Geyser (Yellowstone National Park) from 1870 to 1987. Let x1 be a random variable that represents the time interval (in minutes) between Old Faithful eruptions for the years 1948 to 1952. Based on 9580 observations, the sample mean interval was x1 = 61.8 minutes. Let x2 be a random variable that represents the time interval in minutes between Old Faithful eruptions for the years 1983 to 1987. Based on 23,000 observations, the sample mean time interval was x2 = 69.2 minutes. Historical data suggest that σ1 = 8.49 minutes and σ2 = 11.78 minutes. Let μ1 be the population mean of x1 and let μ2 be the population mean of x2.(a) Compute a 99% confidence interval for μ1 – μ2. (Use 2 decimal places.)
| lower limit | |
| upper limit |
(b) Comment on the meaning of the confidence interval in the context of this problem. Does the interval consist of positive numbers only? negative numbers only? a mix of positive and negative numbers? Does it appear (at the 99% confidence level) that a change in the interval length between eruptions has occurred? Many geologic experts believe that the distribution of eruption times of Old Faithful changed after the major earthquake that occurred in 1959.
Because the interval contains only positive numbers, we can say that the interval length between eruptions has gotten shorter.Because the interval contains both positive and negative numbers, we can not say that the interval length between eruptions has gotten longer. We can not make any conclusions using this confidence interval.Because the interval contains only negative numbers, we can say that the interval length between eruptions has gotten longer.
In: Statistics and Probability
Organism 3
Field Notes: Specimen collected from shaded area along stream in
South Cumberland State Park (Grundy County, TN)
Laboratory Analysis:
Body: Large leaves emerging from underground rhizome
Size: 63cm
Chromosomal Analysis: Plant body is diploid --chromosomes number of
44
Lignin test: Positive
Cuticle: Present
Leaves: Present -- large with branched veins. Underside has
sori(containing haploid spores)
Roots: Present-----branch from the inside
Stem:Present--- vascular tissue(xylem and phloem)present
Life History: Diploid sporophyte dominant generation. Haploid
spores germinate into heart-shaped, haploid, gametophyte. Water
required for fertilization due to flagellated sperm; no seed is
produced. Diploid zygote develops into sporophyte of life ---each
bearing ether megasporangia or microsporangia but not both.
Insects, especially beetles, appear important in
pollination
Question: Explain which domain, kingdom and phylum
you believe this plant should be classified in.
Communication: The local media features the work of your team on their nightly news. During a live interview the reporter asks you " Apparently this plant requires water for fertilization, can you explain, can you explain why"?
Response: ------------------------
In: Biology
HR Industries (HRI) has a beta of 1.9, while LR Industries's (LRI) beta is 1.0. The risk-free rate is 6%, and the required rate of return on an average stock is 13%. The expected rate of inflation built into rRF falls by 1.5 percentage points; the real risk-free rate remains constant; the required return on the market falls to 10.5%; and all betas remain constant. After all of these changes, what will be the difference in the required returns for HRI and LRI? Round your answer to two decimal places.
In: Finance
White Oaks Properties builds strip shopping centers and small malls. The company plans to replace its refrigeration, cooking and HVAC equipment with newer models in one entire center built 11 years ago. 11 years ago, the original purchase price of the equipment was $675,000 and the operating cost has averaged $235,000 per year. Determine the equivalent annual cost of the equipment if the company can now sell it for $234,000. The company's MARR is 22% per year.
The equivalent annual cost of the equipment is determined to be $_________?
In: Economics
Covert a Hexadecimal to decimal (there is a video for you to watch too). Then write a program that can convert a binary to decimal (only for integer case).
There are two ways to do so.
Easy way: Directly use Java built-in method to do this. In this case, only couple lines of code. Hint: Study Integer class in Java.
Hard way: Write your own code to convert a binary to decimal from scratch. The input is a binary string. The program output is its corresponding decimal value. This way you need to design the algorithm.
In: Computer Science
Ch.11- 2. Read the article on DNA origami article ( DNA Origami: The Art of Folding DNA Barbara Sacc* and Christof M. Niemeyer)
Answer each of these questions using 100-150 words
A. What is DNA origami? What has it been used for?
B. What are “staple strands” and how are they used?
C. How can lattices be built in three dimensions?
D. Do a citation index search of publications that reference this paper. What is the most recent citation that uses DNA origami for building novel structures?
In: Chemistry
Use the normal equations to directly apply the least squares method (that is, do not use a transformation or Excel’s built in trendline function) to the given data for the indicated model. Compute D and dmax as bounds for cmax; what do these bounds suggest about improving the fit by using the Chebyshev criterion?
x 1 2 3 4 5
y 1 1 2 2 4
a. y = ax + b
b. y = ax2
Analyze the deviations for each model. Which model is a better fit? Support your conclusions
In: Statistics and Probability
What do Communication Scholars mean when they use the term Self Concept? How does this idea of Self relate to Chapter 8 and Culture? Please describe in detail what Culture means? and How Culture is defined? and How Culture is built? What show did we watch in class to understand this phenomena? How does the show help us to understand the idea of the Self? What conclusions do you draw about your own Culture with a better understanding of Self Concept and Culture?
In: Psychology
Select True or False
True False 1. Conclusions and estimates about a population based on sample data are not always going to be correct. For this reason measures of reliability, such a significance level and confidence level, should be built into the statistical inference.
True False 2. The confidence level is the proportion of times that an estimating procedure will be wrong.
True False 3. Statistical inference is the process of making an estimate, prediction, or decision about a population based on sample data.
True False 4. A summary measure that is computed from a population is called a parameter.
In: Statistics and Probability
Which of the following would be included in inventory? Yes or No
(a) Raw materials costs of leather to a manufacturer of leather furniture
(b) The cost of cans of corn held on the shelves of a grocery store
(c) The cost of a truck in the process of being manufactured by an automobile manufacturer
(d) The cost of land being held for development to a property developer
(e) The cost of a van being used as a courtesy vehicle to an automobile service centre
(f) The costs of construction for a home being built for a specific customer to a builder
(g) The cost of soap and paper towels for the washrooms of a restaurant
In: Accounting