Please correct chosen answers if incorrect.
22) d
23) c
24) c
22) Which of the following is not true regarding event rates:
a. an event can be anything such as Chicago Cubs winning the World Series
b. event rates are seldom used as they only provide data of nominal significance
c. event rate is statistical term that describes how often an event occurs
d. the formula for event rate is the number of times the event occurs, divided by the number of possible times the event could occur
23) Which of the following statements is not true regarding data collection:
a. often times, in our field, we collect data to help us infer or hypothesize about any number of things including treatments, prevention, occurrences, etc
b. collecting count data may be on one single sample or cohort, due to any number of reasons
c. when data is collected on count data, e call the outcome of that collection, results
. in single group studies, control groups are the standard
24) Which of the following statements is true:
a. comparisons between age-adjusted rates can only be useful if the same standard population is used in the creation of the age-adjusted rates
b. event rates are never seen as something which is important in public health except in epidemiological concerns
c. count data is something that is important when considering data gathered on vampires
d. person-time is often used in epidemiological studies in the veterinary sciences
In: Math
Dole Pineapple Inc. is concerned that the 16-ounce can of sliced pineapple is being overfilled. Assume the population standard deviation of the process is .04 ounce. The quality control department took a random sample of 60 cans and found that the arithmetic mean weight was 16.05 ounces. At the 3% level of significance (Step 2), can we conclude that the mean weight is greater than 16 ounces?
Step 1: State the null hypothesis (H0) and the alternate hypothesis (H1). (insert >, >, =,< or <) where appropriate. Ho: ______ 16 H1: _______16
Step 2: you select the level of significance, =.03 (Given in problem description)
Step 3: Identify the test statistic (circle ‘t distribution’ or ‘Normal Curve (z)’) use the t distribution or Normal Curve (z)
Step 4: Formulate the decision rule Reject Ho if _______________________
Step 5: Take a sample arrive at a decision
Step 6: Interpret the results (circle ‘Reject’ or ‘Accept’) circle ‘are’ or ‘are not’) Reject or Accept Ho. The cans are or are not being overfilled.
Please show legible work!
In: Math
An engineer has designed a valve that will regulate water pressure on an automobile engine. The valve was tested on 150 engines and the mean pressure was 4.0 pounds/square inch (psi). Assume the population standard deviation is 0.7 . If the valve was designed to produce a mean pressure of 4.1 psi, is there sufficient evidence at the 0.05 level that the valve does not perform to the specifications? is there sufficient or not sufficient evidence?
In: Math
Find the following probabilities.
A.) P(X=5), X FOLLOWING A BINOMIAL DISTRIBUTION, WITH N=50 AND P=.7.
B.) P(X = 5), X following a Uniform distribution on the interval [3,7].
c.) P(X = 5), X following a Normal distribution, with µ = 3, and σ = .7.
(To complete successfully this homework on Stochastic Models, you need to use one of the software tools: Excel, SPSS or Mathematica, to answer the following items, and print out your results directly from the software. )
In: Math
Problem Set 3: One-Way randomized ANOVA
Research Scenario: A health psychologist is looking into the effects of different kinds of exercise on stress. She divides volunteers into three exercise groups: high-intensity interval training (HIIT) (n=8), yoga (n=8), or running (n=8). The volunteers participate in a set number of hours of the exercise for a month, after which the psychologist measures their stress levels on a scale of 1-40 where lower scores = lower stress, and higher scores = higher stress. The scores for each group are shown in the table below. Input the data into SPSS (remember you will enter the data only using 2 columns - one for group (make sure you label the values) and one fore stress. Conduct a one-way ANOVA to determine the effect of these different exercises on stress levels.
HIIT |
16 |
25 |
19 |
11 |
17 |
11 |
15 |
27 |
YOGA |
19 |
21 |
22 |
23 |
14 |
24 |
27 |
15 |
RUNNING |
19 |
28 |
33 |
24 |
26 |
30 |
17 |
21 |
11) Paste relevant SPSS output
12) Create an appropriate graph to display this data.
13) Write an APA-style Results section based on your analysis. All homework "Results sections" should follow the examples provided in the presentations and textbooks. They should include the statistical statement within a complete sentence that mentions the type of test conducted, whether the test was significant, and if relevant, effect size and/or post hoc analyses. Don't forget to include a decision about the null hypothesis.
In: Math
Fully describe how to use the unified approach for a Poisson distribution describing signal and background events. Illustrate this by constructing a 90% confidence level interval for the number of observed events given a signal yield µ of 2 events and an assumed background of 1 events. You may wish to consider total event yields between zero and ten.
In: Math
Number of Certified Organic Farms in the United States, 2001–2008 |
|
Year | Farms |
2001 | 6,375 |
2002 | 6,730 |
2003 | 7,441 |
2004 | 7,425 |
2005 | 7,882 |
2006 | 8,758 |
2007 | 10,297 |
2008 | 12,019 |
(a) Use Excel, MegaStat, or MINITAB to fit three trends (linear, quadratic, exponential) to the time series. (A negative value should be indicated by a minus sign. Do not round the intermediate calculations. Round your final answers to 2 decimal places.)
Linear | yt = ____ xt + ______ |
Quadratic |
yt = ____ xt2 +_____ xt + _____ |
Exponential | yt = _____ e ____x |
(b) Use each of the three fitted trend equations to make numerical forecasts for the next 3 years. (Round the intermediate calculations to 2 decimal places and round your final answers to 1 decimal place.)
T Linear| Exponential | Quadratic
9 _________ _________ _________
10 _________ _________ _________
11 _________ ___________ _________
In: Math
Why are sampling distributions important to the study of inferential statistics? In your answer, demonstrate your understanding by providing an example of a sampling distribution from an area such as business, sports, medicine, social science, or another area with which you are familiar. Remember to cite your resources and use your own words in your explanation.
(NO PICTURES PLEASE! Text only)
In: Math
Let (X_1, ..., X_k) be a multinomial distribution with probabilities p_1, ..., p_k in n independent trials. Calculate E(X_i), and COV(X_i, X_j) for 1 <= i, j <= k.
In: Math
3. [10 marks] A sample survey of 54 discount brokers showed that the mean price charged for a
trade of 100 shares at $50 per share was $33.77 and a sample standard deviation of $15.
a. [3] Develop a 95% confidence interval for the mean price charged by discount brokers for a trade of 100 shares at $50 per share.
b. [2] Explain, in context, what the interval you found tells you.
c. [3] What sample size would be necessary to achieve a margin of error of $2? Assume a
confidence level of 95%.
d. [2] Three years ago the mean price charged for a trade of 100 shares at $50 per share was
$39.25. Has the price dropped significantly? Justify.
In: Math
You wish to test the following claim ( H a ) at a significance
level of α = 0.002 . H o : p 1 = p 2 H a : p 1 > p 2 You obtain
86.6% successes in a sample of size n 1 = 732 from the first
population. You obtain 79% successes in a sample of size n 2 = 395
from the second population. For this test, you should NOT use the
continuity correction, and you should use the normal distribution
as an approximation for the binomial distribution.
ALL I NEED IS FOR SOMEONE TO SHOW ME HOW TO INPUTE THIS ON A
CALCULATOR TI 84...the 2-PropZ TEST doesnt accept decimals.
In: Math
In a recent Super Bowl, a TV network predicted that 39 % of the audience would express an interest in seeing one of its forthcoming television shows. The network ran commercials for these shows during the Super Bowl. The day after the Super Bowl, and Advertising Group sampled 105 people who saw the commercials and found that 40 of them said they would watch one of the television shows. Suppose you are have the following null and alternative hypotheses for a test you are running: H 0 : p = 0.39 H a : p > 0.39
In: Math
To identify regional groupings of market segments it is useful to use which of the following research tools? Select one: a. Cluster analysis b. Factor analysis c. Simple random sampling d. Open-ended questions
The following marketing research technique(s) is used for perceptual mapping: Select one: a. correlation and regression b. conjoint analysis c. t-tests and ANOVA d. multidimensional scaling
In: Math
Toyota company prides themselves on customer service. they have been trying to determine exactly how long it takes, from start to finish, to buy a car at their dealerships. they have determined that the two parts of the transaction (showroom and service) follow the normal model. showroom has a mean time of 3.5 hours with a standard deviation of 1.5 hours. service has an average time of 2 hours with a standard deviation of 0.5 hours.
a) What is the mean and standard deviation of the difference between the showroom and service average waiting time.
b) What is the probability that it will take a customer longer during the service portion of the transaction.
c) Why does the standard deviation always increase when we add or subtract the means of two distributions.
In: Math
There are 3 SPSS outputs in this homework assignment. The questions for each output are listed below. Please type your answers into this word document and submit it as an attachment in the assignment tab.
Q1. Researchers were interested in determining whether background music helped or hindered students’ performance on a math test. Students were randomly assigned to 1 of 3 groups: 1) no music; 2) music only; and 3) music with lyrics. Students were then given a math exam, scores which could range from 0 to 100.
N |
Mean |
Std. Deviation |
Std. Error |
95% Confidence Interval for Mean |
||
Lower Bound |
Upper Bound |
|||||
No music |
250 |
77.59 |
13.055 |
.826 |
75.96 |
79.21 |
Music only |
250 |
78.10 |
13.357 |
.845 |
76.44 |
79.77 |
Music and lyrics |
250 |
78.97 |
13.263 |
.839 |
77.32 |
80.62 |
Total |
750 |
78.22 |
13.221 |
.483 |
77.27 |
79.17 |
ANOVA |
|||||
minutes |
|||||
Sum of Squares |
df |
Mean Square |
F |
Sig. |
|
Between Groups |
244.595 |
2 |
122.297 |
.699 |
.497 |
Within Groups |
130668.664 |
747 |
174.925 |
||
Total |
130913.259 |
749 |
In: Math