The heart rate variability (HRV) of police officers was the subject of research published in a biology journal. HRV is defined as the variation in the time intervals between heartbeats. A measure of HRV was obtained for each in a sample of 331 police officers from the same city. (The lower the measure of HRV. the more susceptible the officer is to cardiovascular disease.) For the 76 officers diagnosed with hypertension, a 90% confidence interval for the mean HRV was (7.2,121.3). For he 255 officers that are not hypertensive, a 90% confidence interval for the mean HRV was (141.6,189.9). Use this information to complete parts a through d below. a. What confidence coefficient was used to generate the confidence intervals? (Type an integer or a decimal. Do not round) . Give a practical interpretation of both of the 90% confidence intervals. Use the phrase "90% confident" in your answer. The researchers can be 90% confident that the V mean HRV for all hypertensive police officers in the V is between and A similar statement can be made about the police officers without hypertension. Type integers or decimals. Do not round.) . When you say you are "90% confident," what do you mean? OA. The phrasing "90% confident" means that 90% of the sample data will fall between the bounds of the confidence interval. O B. The phrasing "90% confident" means that similarly collected samples will be approximately normal 90% of the time. OC. The phrasing "90% confident" means that there is a 90% chance that the sample data was collected in such a way that the bounds of the confidence interval can be trusted. O D. The phrasing "90% confident" means that 90% of confidence intervals constructed from similarly collected samples will contain the true population mean. 1. If you want to reduce the width of each confidence interval, should you use a smaller larger confidence coefficient? Explain. confidence coefficient should be used. This will result in a V and thus a narrower confidence interval.

Recently, researchers have begun to focus on the relationship between potentially toxic environmental exposures in children to a number of adverse health outcomes. Suppose one such researcher wants to investigate the relationship between lead levels in soil (micrograms/dL) and BMI (kg/m2). The following table represents a SRS of households with the corresponding exterior lead levels and BMI of a randomly sampled child in the home.Leal levels (μg/dL) 13.614.39.79.4 11.4 10.9BMI (kg/m2) 19.719.920.122.1 19.8 21.6A) Write out the null and alternative hypotheses for a formal test of significance testing the correlation between the two variables.B) Calculate a t statistic and interpret your pvalue and results.

Binge-watching a television show might not be the best way to enjoy a television series (Horvath et al., 2017). Participants in an experiment were in a group that either watched an entire t.v. series during daily one-hour sessions or watched all the episodes during a single binge session. Participants were asked to rate their enjoyment of the t.v. series on a scale of 0-100. Data like those observed by the author are listed below.        Binge-watched          Daily-watched                87                              84                71                              100                73                              87                86                              97                78                              92   Is there a difference in the level of enjoyment based on whether the series was binge-watched or watched on a daily basis? Use a two-tailed test at the α = 0.05 level of significance?

A physical therapist wanted to know whether the mean step pulse of men was less than the mean step pulse of women. She randomly selected 54 men and 75 women to participate in the study. Each subject was required to step up and down a 6-inch platform. The pulse of each subject was then recorded. The following results were obtained. Two sample I for Men vs Women Mean 112.8 118.1 StDev SE Mean Men Women 95% Cl for mu Men - mu Women (-9.81, - 0.79) T-Test mu Men = mu Women (vs <) T= - 2,34 P = 0.0104 DF = 126 54 11.2 14.5 1.5 75 1.7 P-value = 0.0104 State the researcher's conclusion. Which of the following is correct? O A. Fail to reject Ho, there is sufficient evidence to conclude that the mean step pulse of men was less than the mean step pulse of women O B. Reject Ho, there is not sufficient evidence to conclude that the mean step pulse of men was less than the mean step pulse of women O C. Fail to reject Ho, there is not sufficient evidence to conclude that the mean step pulse of men…

In hundreds of studies with many thousands of participants, first-born children scored better than second born children on tests of cognitive ability. Data based on previous research provides mean scores of 469 for first born and 456 for second born. The cognitive ability standard deviation is 100. Find effect size and interpretation.

Miss America winners from the 1920's and 1930's had a average BMI of 19.4. A sample of recent winners had reported BMIs of 18.7, 18.7, 18.5, 19.2, 19.3, 18.7, 18.6, 19.8, 19, 19.6, and 19 . Do recent winners appear to be significantly different from those in the 1920s and 1930s? (assume normality). Show all the steps of a hypothesis.

A scientist is studying the effect of a new type of exercise program on cardiovascular health. The scientist randomly assigns individuals to either the exercise program or a control group. The scientist wants to determine if the exercise program has a statistically significant effect on cardiovascular health. The scientist monitors cardiovascular health by measuring the blood pressure of each individual.

A clinical psychologist is investigating the relationship between sleep and feelings ofanxiety. For a sample of 15 individuals, he asks each participant to indicate how many hours theytypically sleep each night and each participant also completes an anxiety assessment. The followingdata is obtained:Hours of sleep: M=6.0 SS=16.0Anxiety scores: M=8.0 SS=64.0SP = - 20.0 a. Compute the correlation between hours of sleep and anxiety scores.

Which of the following sets of data is most likely to produce a significant t statistic? Select one: MD = 10, SS = 100 MD = 10, SS = 10 MD = 2, SS = 10 MD = 2, SS = 100

A physical therapist wanted to know whether the mean step pulse of men was less than the mean step pulse of women. She randomly selected 54 men and 70 women to participate in the study. Each subject was required to step up and down a 6-inch platform. The pulse of each subject was then recorded. The following results were obtained. Two sample T for Men vs Women N Mean StDev SE Mean Men Women 98% CI for mu Men - mu Women (- 12.20, - 1.00) T-Test mu Men = mu Women (vs H2 O C. Ho: H1 = H2; Ha: H1 #H2 (b) Identify the P-value and state the researcher's conclusion if the level of significance was a = 0.01. What is the P-value? P-value =