The following data contains the data for a group of participants that took a timed test. The data are the average amount of time the participants took on each item (response time) and the number of guesses it took to get each item correct (number correct).
Do this using SPSS; make sure you show your output data as well as your responses to the following questions.
A. What is the regression equation for predicting response time from number correct?
B. What is the predicted response time if the number correct is 8?
C. Based upon the p-value, would you reject the null or accept the null? Explain your decision and what this tells us.
TIME |
CORRECT |
TIME |
CORRECT |
14.5 |
5 |
13.9 |
3 |
13.4 |
7 |
17.3 |
12 |
12.7 |
6 |
12.5 |
5 |
16.4 |
2 |
16.7 |
4 |
21 |
4 |
22.7 |
3 |
In: Math
The Tire Rack, America's leading online distributor of tires and wheels, conducts extensive testing to provide customers with products that are right for their vehicle. The following data show survey ratings (1 to 10, with 10 being the highest) for 18 summer tires. Develop an estimated regression equation that can be used to predict the Buy Again rating given based on the Steering and Tread wear rating. How many percent of the variation in the Buy Again variable could be predicted by Steering and Thread wear rating?
Note: put answers into decimal form, if your answer is 90.8765%, enter in 0.908765.
In: Math
You intend to estimate a population mean with a confidence interval. You believe the population to have a normal distribution. Your sample size is 9.
Find the critical value that corresponds to a confidence level of 98%. Report answer accurate to three decimal places with appropriate rounding.
In: Math
A population of values has a normal distribution with μ = 109.2 and σ = 65.6 . You intend to draw a random sample of size n = 90 .
Find the probability that a sample of size n = 90 is randomly selected with a mean greater than 96.1. P( ¯ x > 96.1) =
Enter your answers as numbers accurate to 4 decimal places. Answers obtained using exact z-scores or z-scores rounded to 3 decimal places are accepted. License
In: Math
n 1944, an organization surveyed 1100 adults and asked, "Are you a total abstainer from, or do you on occasion consume, alcoholic beverages?" Of the 1100 adults surveyed, 396 indicated that they were total abstainers. In a recent survey, the same question was asked of 1100 adults and 374 indicated that they were total abstainers. Complete parts (a) and (b) below. (a) Determine the sample proportion for each sample. The proportions of the adults who took the 1944 survey and the recent survey who were total abstainers are nothing and nothing, respectively. (Round to three decimal places as needed Has the proportion of adults who totally abstain from alcohol changed. Use the a=0.10 level of significance Determine the null and alternative hypothesis Find the test statistics for this hypothesis test Interpret the P value State conclusion for hypothesis test
In: Math
Is the difference between the mean annual salaries of statisticians in Region 1 and Region 2 more than $8000? To decide, you select a random sample of statisticians from each region. The results of each survey are shown to the right. At α=0.10, what should you conclude? Answer A-E
Region 1
x1 = $68,300
standard deviation = $8,750
n1 = 47
Region 2
x2 = $63,000
standard deviation = $9,275
n2 = 40
A. What are the alternative and null hypotheses? Express them mathematically.
B. Determine the critical values and rejection regions
C. Calculate the standardized test statistic
D. Choose the correct answer below
a) Fail to reject H null, at the 1% significance level, there is sufficient evidence to support the claim that the difference between the mean annual salaries is more than $8000
b) Reject H null, at the 1% significance level, there is sufficient evidence to support the claim that the difference between the mean annual salaries is more than $8000
c) Reject H null, at the 1% significance level, there is insufficient evidence to support the claim that the difference between the mean annual salaries is more than $8000
d) Fail to reject H null, at the 1% significance level, there is insufficient evidence to support the claim that the difference between the mean annual salaries is more than $8000
In: Math
A study reports that 36% of companies in a Country A have three or more female board directors. Suppose you select a random sample of 100 respondents.
What is the probability that the sample will have between 29% and 38% of companies in Country A that have three or more female board directors?
In: Math
a. What is the null hypothesis?
b. What is the research hypothesis?
c. Why run a Two-Sample Assuming Equal Variances t-test?
d. Interpret the findings. What are the results of the hypothesis test? Can you reject the null hypothesis?
In: Math
Insomnia and Education. A random-digit telephone dialing procedure was employed to collect data on 575 study participants. The researcher classified each participant into one of four education categories (college graduate, some college, high school graduate, and high school dropout) as well as two categories of insomnia status (normal sleeper or chronic insomnia). One dependent variable of interest to the researchers was a quantity measure of daytime functioning called the Fatigue Severity Scale (FSS). The data were analyzed using an ANOVA model a Write the model underlying the analysis bThe researcher reported that “the Insomnia×Education interaction was not statistically significant”. Interpret this result in context. Illustrate with a graph. (4 Marks c The researchers discovered that the mean FSS was significantly greater for normal sleepers than for people with chronic insomnia. Interpret this result in context. d The researcher reported that the main effect of Education was statistically significant. Interpret this result in context.
In: Math
In: Math
In: Math
Use EXCEL and formulas
Linear program problem whose output follows determines how many necklaces, bracelets, rings, and earrings a jewelry store should stock. The objective function measures profit; it is assumed that every piece stocked will be sold. Constraint 1 measures display space in units, constraint 2 measures time to set up the display in minutes. Constraints 3 and 4 are marketing restrictions.
MAX 100X1+120X2+150X3+125X4
S.T.
1) X1+2X2+2X3+2X4<108
2) 3X1+5X2+X4<120
3) X1+X3<25
4) X2+X3+X4>50
Use the microsoft excel solver method to find the solution and the
sensitivity report.
Which resource should the company increase and why?
In: Math
Use the Financial database from “Excel Databases.xls” on Blackboard. Use Total Revenues, Total Assets, Return on Equity, Earnings Per Share, Average Yield, and Dividends Per Share to predict the average P/E ratio for a company. Use Excel to perform a forward selection regression analysis. Assume a 5% level of significance. Based on your final model, what is the p-value from the test of the overall model? Write your answer as a number and round to 3 decimal places.
Excel Data: https://drive.google.com/file/d/1TQG5r2wzLGk--75whZXyb0SDTHZTWS0S/view?usp=sharing
In: Math
A television station wishes to study the relationship between
viewership of its 11 p.m. news program and viewer age (18 years or
less, 19 to 35, 36 to 54, 55 or older). A sample of 250 television
viewers in each age group is randomly selected, and the number who
watch the station’s 11 p.m. news is found for each sample. The
results are given in the table below.
Age Group | |||||
Watch 11 p.m. News? |
18 or less | 19 to 35 | 36 to 54 | 55 or Older | Total |
Yes | 49 | 52 | 67 | 79 | 247 |
No | 201 | 198 | 183 | 171 | 753 |
Total | 250 | 250 | 250 | 250 | 1,000 |
(a) Let p1,
p2, p3, and
p4 be the proportions of all viewers in each
age group who watch the station’s 11 p.m. news. If these
proportions are equal, then whether a viewer watches the station’s
11 p.m. news is independent of the viewer’s age group. Therefore,
we can test the null hypothesis H0 that
p1, p2,
p3, and p4 are equal by
carrying out a chi-square test for independence. Perform this test
by setting α = .05. (Round your answer to 3 decimal
places.)
χ2
=
so
H0: independence
(b) Compute a 95 percent confidence interval for
the difference between p1 and
p4. (Round your answers to 3 decimal
places. Negative amounts should be indicated by a minus
sign.)
95% CI: [ , ]
In: Math
You are interested in understanding whether mentally ill offenders are better able to avoid re-arrest if they are assigned a mental health case manager upon their release from jail or prison. You study a sample of formerly incarcerated people with mental health diagnoses. You are comparing people with a case manager to those who do not have one (measured as: has a case manager / does not have a case manager), on whether or not they are re-arrested within one year (measured as two categories: rearrested vs. not re-arrested). 1. Write a one-tailed, directional research hypothesis that is appropriate for the above research project. 2. Specify your dependent and independent variables, and at what level they are measured. 3. Write the corresponding null hypothesis for this research study. 4. Specify the type of statistical test you would use in this situation and why. 5. Assume that you find that 50% of people with a case manager are re-arrested, and 60% of people without a case manager are re-arrested within one year. If your statistical analysis produced a test value of 2.70 (and you have 1 df), what would this tell you (assuming you use alpha=.05 as the cut-off for your rejection region)? 6. Write up your results as if you were reporting them in an official report. Examples of appropriate write-ups are available in the videos and powerpoints for each kind of statistical test.
In: Math