Please answer all parts of the question, with all work shown
Suppose there are 300 cards in a box numbered 1 through 300. Therefore, the number of each card has one, two, or three digits. A card is drawn at random from the box. Suppose that the number on the card has X digits of which Y are 0. Suppose we would like to know whether X and Y are correlated, negatively correlated, or uncorrelated. Determine Cov(X,Y)Cov(X,Y) and ρ(X,Y)ρ(X,Y), hence settling the question.
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"Unknown cultural affiliations and loss of identity at high elevations." These are words used to propose the hypothesis that archaeological sites tend to lose their identity as altitude extremes are reached. This idea is based on the notion that prehistoric people tended not to take trade wares to temporary settings and/or isolated areas. As elevation zones of prehistoric people (in what is now the state of New Mexico) increased, there seemed to be a loss of artifact identification. Consider the following information. Elevation Zone Number of Artifacts Number Unidentified 7000-7500 ft 113 73 5000-5500 ft 145 20 Let p1 be the population proportion of unidentified archaeological artifacts at the elevation zone 7000-7500 feet in the given archaeological area. Let p2 be the population proportion of unidentified archaeological artifacts at the elevation zone 5000-5500 feet in the given archaeological area. (a) Find a 95% confidence interval for p1 − p2. (Round your answers to three decimal places.)
lower limit=
upper limit=
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Suppose individual X scores in the population follow a normal distribution N(38, 20). A researcher draws numerous samples of sample size n = 100 from the population, and in each sample, she calculates the sample mean. Then 68% of these sample means should approximately fall within Group of answer choices (A) 34 and 40 (B) 34 and 38 (C) 38 and 44 (D) 36 and 40
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In this hypothetical case study, a new rapid test kit nicknamed Alpha is being reviewed. The sensitivity of Alpha is 93.0% (0.93) and the specificity is 96.0% (0.96). Assume that the actual prevalence of the Zika antibody among the United States population of blood donors is 4% (0.04) and that of the hurricane disaster relief volunteers returning from Puerto Rico is 20.0% (0.20).
Construct a separate 2 x 2 table, to calculate the PPV and NPV for a population of 2,500 volunteers who aided in the recent hurricane relief efforts in the Caribbean.
If sensitivity and specificity remain constant, what is the relationship of prevalence to predictive-value positive and predictive-value negative? (Hint: Think if one increases, decreases, or stays the same.)
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Let X~Bin(100,0.5).
Show all workings in details
a) Find the probability that X is a perfect square.
b) Find the probability that X is a greater than 60.
c) Find the expected value and variance of X.
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1. A pharmacy is using X bar and R charts to record the time it takes to fill a prescription after the customer has turned in or called in the prescription. Each day, the pharmacy records the times it takes to fill six prescriptions. During a 30-day period, the hospital obtained the following values: X double bar = 20 minutes; R bar = 4 minutes. The upper and lower specifications are 23 minutes and 13 minutes respectively. What is the value of 6 sigma, to one decimal place?
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Based on a recent study, the pH level of the arterial cord (one vessel in the umbilical cord) is normally distributed with mean 7.36 and standard deviation of 0.11. Find the percentage of preterm infants who have the following arterial cord pH levels.
a. pH levels between 7.00 and 7.50.
b. pH levels over 7.44.
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A pharmaceutical company is testing a new drug to increase memorization ability. It takes a sample of individuals and splits them randomly into two groups. After the drug regimen is completed, all members of the study are given a test for memorization ability with higher scores representing a better ability to memorize. Those 23 participants on the drug had an average test score of 31.622 (SD = 4.794) while those 21 participants not on the drug had an average score of 32.04 (SD = 5.335). You use this information to create a 95% confidence interval for the difference in average test score. What is the margin of error? Assume the population standard deviations are equal.
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2. The dataset QuizPulse10 contains pulse rates collected from 10 students in a class lecture and then from the same ten students during a quiz. We might expect the mean pulse rate to increase under the stress of a quiz. Use the dataset to test at the 5% significance level whether there is evidence to support this claim.
a. Perform the hypothesis test in Minitab.
b. Make a decision and mathematically justify your decision
c. Interpret the results.
| student | quiz | lecture |
| 1 | 75 | 73 |
| 2 | 52 | 53 |
| 3 | 52 | 47 |
| 4 | 80 | 88 |
| 5 | 56 | 55 |
| 6 | 90 | 70 |
| 7 | 76 | 61 |
| 8 | 71 | 75 |
| 9 | 70 | 61 |
| 10 | 66 | 78 |
In: Math
|
Sales of People magazine are compared over a 5-week period at four Borders outlets in Chicago. |
| Weekly Sales | |||
| Store 1 | Store 2 | Store 3 | Store 4 |
| 103 | 98 | 89 | 105 |
| 104 | 77 | 94 | 117 |
| 105 | 83 | 75 | 86 |
| 112 | 82 | 104 | 104 |
| 114 | 98 | 91 | 98 |
|
Fill in the missing data. (Round your p-value to 4 decimal places, mean values to 1 decimal place, and other answers to 3 decimal places.) |
| Treatment | Mean | n | Std. Dev |
| Store 1 | |||
| Store 2 | |||
| Store 3 | |||
| Store 4 | |||
| Total | |||
| One-Factor ANOVA | |||||
| Source | SS | df | MS | F | p-value |
| Treatment | |||||
| Error | |||||
| Total | |||||
| (a) | Based on the given hypotheses choose the correct option. |
| H0: μ1 = μ2 = μ3 = μ4 | |
| H1: Not all the means are equal | |
| α = 0.05 | |
| |
|
|
| (b) | Determine the value of F. (Round your answer to 2 decimal places.) |
| F-value |
| (c) |
On the basis of the above-determined values, choose the correct decision from below. |
|
| (d) | Determine the p-value. (Round your answer to 4 decimal places.) |
| p-value |
In: Math
Do out-of-state motorists violate the speed limit more frequently than in-state motorists? This vital question was addressed by the highway patrol in a large eastern state. A random sample of the speeds of 2,500 selected cars was categorized according to whether the car was registered in the state or in some other state and whether or not the car was violating the speed limit. The data follow.
In state speeding cars: 521
Out of state speeding cars: 328
In state not speeding cars: 1141
Out of state not speeding cars: 510
a.) Do these data provide enough evidence to support the highway patrol's claim at the 5% significance level? Your conclusion must be in terms of the P-Value. Show all necessary work.
b). What type of error is possible and describe this error in terms of the problem?
c). Estimate the difference in the actual percentage of In State and Out of State speed limit violators using a 95% confidence interval. Show all necessary work. Using this interval estimation, is there sufficient evidence to support the highway patrol's claim? Explain Carefully.
d). Carefully interpret the confidence interval estimation.
In: Math
|
Employee Number |
Time 1 Satisfaction |
Time 2 Satisfaction |
|
10012 |
8.5 |
6.5 |
|
10057 |
6.8 |
4 |
|
10089 |
6.5 |
4 |
|
10126 |
4.2 |
5.7 |
|
10023 |
7 |
6 |
|
10045 |
6 |
3 |
|
10094 |
7 |
6.5 |
|
10087 |
3 |
3 |
|
10145 |
4.5 |
3.5 |
|
10023 |
9 |
8.5 |
|
10062 |
8.5 |
4 |
|
10078 |
4 |
2.5 |
In: Math
For a data set obtained from a sample of size n = 121
with x- = 44.25, it is known that σ = 5.4.
(a) What is the point estimate of
µ?
(b) Find z score corresponding to a 95%
confidence level, zα/2. Recall that
(1 − α)100% = 95%.
(c) Construct a 95% confidence interval for
µ.
(d) What is the margin of error in part
(c)?
In: Math
In: Math
Chi-square tests are nonparametric tests that examine nominal categories as opposed to numerical values. Consider a situation in which you may want to transform numerical scores into categories. Provide a specific example of a situation in which categories are more informative than the actual values.
Suppose we had conducted an ANOVA, with individuals grouped by political affiliation (Republican, Democrat, and Other), and we were interested in how satisfied they were with the current administration. Satisfaction was measured on a scale of 1-10, so it was measured on a continuous scale. Explain what changes would be required so that you could analyze the hypothesis using a chi-square test. For instance, rather than looking at test scores as a range from 0 to 100, you could change the variable to low, medium, or high. What advantages and disadvantages do you see in using this approach? Which is the better option for this hypothesis, the parametric approach or nonparametric approach? Why?"
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