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The Left Ventricular Mass lndex (LVMI) is a measure of the enlargement of the left side of the heart and is expressed in the units (gm/ht(m)2.7). High values may predict subsequent cardiovascular disease in children as they get older (Urbina et al., [11]). A study is performed to relate the level of LVMI to blood pressure category in children and adolescents age 10–18. The bp level of children was categorized as either Normal (bpcat = 1 or bp percentile < 80% for a given age, gender, and height), Pre-Hypertensive (bpcat = 2 or bp percentile ≥ 80% and bp percentile < 90%), or Hypertensive (bpcat = 3 or bp percentile ≥ 90%). The data are available in the data set LVM.XLS at www.cengagebrain.com
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- Find the mean hourly cost when the cell phone described above is used for 240 minutes.arrow_forwardGlaucoma is a leading cause of blindness in the United States, N. Ehlers measured the difference in corneal thickness (in microns) between the two eyes of eight patients. Each patient had one eye that had glaucoma and one eye that was normal. The difference was measured as the corneal thickness of normal eye – corneal thickness of eye with Glaucoma. Corneal thickness is important because it can mask an accurate reading of eye pressure. Question:If the t statistic falls below the effect size in which we reject the null, but the p value is greater than 0.05. Do i reject the null? As my scenario had no population mean because the differences were recorded, do i set a test value of 10 or keep it at 0?arrow_forwardA researcher wonders whether younger mothers have babies that are significantly heavier or lighter than the population average of μ 7.25 pounds. The researcher collects data from N = 35 babies who were born to mothers between the ages of 16 and 18. The average weight for these babies was M = 7.15 pounds (SD = .6 pounds).arrow_forward
- Heart rate during laughter. Laughter is often called “the best medicine,” since studies have shown that laughter can reduce muscle tension and increase oxygenation of the blood. In the International Journal of Obesity (Jan. 2007), researchers at Vanderbilt University investigated the physiological changes that accompany laughter. Ninety subjects (18–34 years old) watched film clips designed to evoke laughter. During the laughing period, the researchers measured the heart rate (beats per minute) of each subject, with the following summary results: Mean = 73.5, Standard Deviation = 6. n=90 (we can treat this as a large sample and use z) It is well known that the mean resting heart rate of adults is 71 beats per minute. Based on the research on laughter and heart rate, we would expect subjects to have a higher heart beat rate while laughing.Construct 95% Confidence interval using z value. What is the lower bound of CI? a) Calculate the value of the test statistic.(z*) b) If…arrow_forwardA researcher is interested in testing the relationship between smoking and BMI (kg/m2) in adults aged 30-45. In order to test this association, the researcher divides smoking into currently more than a pack a day, currently less than a pack a day, and never smokers. The following table represents the BMIs for each participant enrolled by their respective smoking category. Current Smoker (≥1pack/day) Current Smoker (<1 pack/day Never Smoked 26.7 29.4 22.1 29.4 28.6 30.4 24.3 27.4 21.3 28.4 23.2 26.4 21.6 20.1 19.7 27.4 20.6 19.8 26.8 19.7 21.6 36.4 19.6 22.3 31.5 21.6 24.3 27.4 21.5 *Continue as though all assumptions for ANOVA are met. A) Calculate the MSW and MSB for the data represented above. B) Carry out a formal test for a one-way analysis of variance among the groups and interpret your results.arrow_forwardWhat does am/n mean ?arrow_forward
- Sulfur compounds cause "off‑odors" in wine, so winemakers want to know the odor threshold, the lowest concentration of a compound that the human nose can detect. The odor threshold for dimethyl sulfide (DMS) in trained wine tasters is about 25 micrograms per liter of wine (?g/L ). The untrained noses of consumers may be less sensitive, however. The DMS odor thresholds for 10 untrained students are given. 30 30 42 35 22 33 31 29 19 23 (a) Assume that the standard deviation of the odor threshold for untrained noses is known to be ?=7?g/Lσ To access the complete data set, click the link for your preferred software format: Do the three simple conditions hold in this case? Make a stemplot and use it to check the shape of the distribution. (b) STATE: What is the average (mean) DMS odor threshold, ?μ , for all untrained people? PLAN: Using the four‑step process, give a 95%95% confidence interval for the mean DMS odor threshold among all students. SOLVE: We have assumed that we…arrow_forwardwhat is the difference between t-statistic and z-statistic ? Compare the t-statistic formula and the z-statistic formula?arrow_forward“Normal” BMI is up to 25 kg/m2. A laboratory study is being conducted to determine energy expenditure for those who are overweight and/or obese. The researchers have enrolled only subjects with BMI above 25.0 and have quantified obesity as “units above normal”. For example, a subject with BMI of 32.3 is recorded as 7.3 (i.e. 32.3 – 25.0 = 7.3). Using this scheme, the mean obesity was found to be 8.7 kg/m2and the standard deviation was 6.4 kg/m2. If we convert the obesity measure used in this study back into conventional BMI (i.e., add 25.0 units to each measurement), what will the standard deviation be? Group of answer choices The standard deviation will be larger on the BMI scale because 25.0 units will be added back. The standard deviation will be the same 6.4 kg/m2 There is not enough information to determine this The standard deviation will be smaller on the BMI scale because, as a percentage of the whole scale, the difference between each subject and the mean will be…arrow_forward
- Ankle Brachial Index. The ankle brachial index (ABI) compares the blood pressure of a patient’s arm to the blood pressure of the patient’s leg. The ABI can be an indicator of different diseases, including arterial diseases. A healthy (or normal) ABI is 0.9 or greater. In a study by M. McDermott et al. titled “Sex Differences in Peripheral Arterial Disease: Leg Symptoms and Physical Functioning” (Journal of the American Geriatrics Society, Vol. 51, No. 2, pp. 222–228), the researchers obtained the ABI of 187 women with peripheral arterial disease. The results were a mean ABI of 0.64 with a standard deviation of 0.15. At the 1% significance level, do the data provide sufficient evidence to conclude that, on average, women with peripheral arterial disease have an unhealthy ABI?arrow_forwardHow sensitive to changes in water temperature are coral reefs? To find out, scientists examined data on sea surface temperatures and coral growth per year at locations in the Gulf of Mexico and the Caribbean Sea. Scientists examined data on mean sea surface temperatures (in degrees Celsius) and mean coral growth (in centimeters per year) over a several‑year period at locations in the Gulf of Mexico and the Caribbean. The table shows the data for the Gulf of Mexico. Sea surface temperature 26.726.7 26.626.6 26.6 26.526.5 26.326.3 26.126.1 Growth 0.850.85 0.850.85 0.790.79 0.860.86 0.890.89 0.920.92 (a) Use software to find the mean and standard deviation of both sea surface temperature ?x and growth ?y and then find the correlation ?r between ?x and ?.y. Enter your answers in the answer fields using the specific decimal place precision noted. ?¯ (rounded to four decimal places)=x¯ (rounded to four decimal places)= ?? (rounded to four decimal places)=sx…arrow_forwarda study was done involving data from all major US cities that compares the number of parks in each city to the average number of times an individual exercises each week. Pearson's r=.76 What does the value of r suggest?arrow_forward
- Glencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw HillCollege Algebra (MindTap Course List)AlgebraISBN:9781305652231Author:R. David Gustafson, Jeff HughesPublisher:Cengage LearningHolt Mcdougal Larson Pre-algebra: Student Edition...AlgebraISBN:9780547587776Author:HOLT MCDOUGALPublisher:HOLT MCDOUGAL