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In one study on the effect of Dyazide on blood pressure level, 200 subjects who reported taking Dyazide for a long period of time had their blood pressure levels compared with those of 200 people who had never taken Dyazide. In a second study, 25 subjects were randomly chosen to receive Dyazide and 25 were chosen to receive a placebo.Which of the following statement is correct?

Select the term that best fits this definition: As n increases the shape of the distribution will look more and more like a normal distribution

In One Sample Proportion test, it is important to convert the sample proportion to a z-score first. In this example, we selected a random sample of size 130 from a pool of university students and asked whether they use the university gym on a regular basis. Ninety replied yes. Assuming that the population proportion under the null hypothesis is 50%, what is the z-score (test statistics) for the sample proportion?

Select the term that best fits this definition: This equals the expected value of a sample mean for a sampling distribution

A researcher would like to study BMI levels in adults 20-40 years of age. She selected 9 patients and found their BMI values to be: 25, 19, 28, 30, 32, 37, 22, 27, 24The standard deviation of BMI levels of this group of patients is

Using the information below calculate the predicted value for Y for the given value of X. Y (Dependent Variable) = Grade Point Average X (Independent Variable) = Average number of hours spent using electronic devices for entertainment purposes   yhat = 4 – 0.125*X   On average what would a person’s Grade Point Average be if they spend on average 8 hours using electronic devices for entertainment purposes (round your answer to 4 decimal places)?

To compare the treatment effects of two interventions, two independent samples of patient medical data were collected. The sample sizes are 20 and 26 respectively. Assuming that the two populations shared the same variance, the researchers decided to conduct a two independent samples test for the means. What would be the number of degrees of freedom for the obtained t statistic with these sample sizes?

the coefficient of correlation r and the slope of the regression line:

Which of the following statements are true regarding Type I or Type II errors?

It is known that incomes from the USA follow a normal distribution with a mean of $55,000 and a standard deviation of $12,000.  A researcher took a sample of 1000 people in the USA and obtained a sample mean of $67,000 with a standard deviation of $18,000.  What are the characteristics of the sampling distribution.