# Study Design Probability Questions & Answers

Recent questions in Study design
vashikagreene 2022-06-19

### The physical plant at the main campus of a large state university recieves daily requests to replace florecent lightbulbs. The distribution of the number of daily requests is bell-shaped and has a mean of 60 and a standard deviation of 7. Using the empirical rule (as presented in the book), what is the approximate percentage of lightbulb replacement requests numbering between 53 and 60?Do not enter the percent symbol.ans =

vashikagreene 2022-06-17

### The physical plant at the main campus of a large state university recieves daily requests to replace florecent lightbulbs. The distribution of the number of daily requests is bell-shaped and has a mean of 60 and a standard deviation of 7. Using the empirical rule (as presented in the book), what is the approximate percentage of lightbulb replacement requests numbering between 53 and 60?Do not enter the percent symbol.ans =

Mike Jacob 2022-06-07

### what statistic would you use if you had one independent variable, geographic location (north, south, east, west), and one dependent variable (satisfaction with the living environment, yes or no)?

Mike Jacob 2022-06-07

### what statistic would you use if you had one independent variable, geographic location (north, south, east, west), and one dependent variable (satisfaction with the living environment, yes or no)?

Study design Answered
erurnSopSoypegx 2021-11-23

### A researcher was interested in knowing whether the mean weight of the second baby is higher, lower, or about the same as the mean weight of the first baby for women who have at least two children

Study design Answered
BolkowN 2021-10-25

### In a study designed to prepare new gasoline-resistant coatings, a polymer chemist dissolves 6.053 g of polyvinyl alcohol) in enough water to make 100.0 mL of solution. At ${25}^{\circ }C$, the osmotic pressure of this solution is 0.272 atm. What is the molar mass of the polymer sample?

Study design Answered
nagasenaz 2021-10-11

### Which of the following types of studies require approval by an Internal Review Board? (Pick more than one) 1) Research that poses risks to participants 2) Surveys not meant to be published 3) Data collected for instructional purposes only 4) Data collected through phones or computers 5) Data collected on vulnerable populations

Study design Answered
BenoguigoliB 2021-08-14

### The pathogen Phytophthora capsici causes bell pepper plants to wilt and die. A research project was designed to study the effect of soil water content and the spread of the disease in fields of bell peppers. It is thought that too much water helps spread the disease. The fields were divided into rows and quadrants. The soil water content (percent of water by volume of soil) was determined for each plot. An important first step in such a research project is to give a statistical description of the data. Soil Water Content for Bell Pepper Study $\begin{array}{ccccccccccccccc}15& 14& 14& 14& 3& 12& 11& 11& 11& 11& 10& 11& 13& 16& 10\\ 9& 15& 12& 9& 10& 7& 14& 13& 14& 8& 9& 8& 11& 13& 13\\ 15& 12& 9& 10& 9& 9& 16& 16& 12& 10& 11& 11& 12& 15& 8\\ 10& 10& 10& 11& 9\end{array}$ (a) Make a box-and-whisker plot of the data. Find the interquartile range.

Study design Answered
sibuzwaW 2021-08-12

### State whether the investigation in question is an observational study or a designed experiment. Justify your answer in each case.In the 1940s and early 1950s, the public was greatly concerned about polio. In an attempt to prevent this disease, Jonas Salk of the University of Pittsburgh developed a polio vaccine. In a test of the vaccine’s efficacy, involving nearly 2 million grade-school children, half of the children received the Salk vaccine. the other half received a placebo, in this case an injection of salt dissolved in water. Neither the children nor the doctors performing the diagnoses knew which children belonged to which group, but an evaluation center did. The center found that the incidence of polio was far less among the children inoculated with the Salk vaccine. From that information, the researchers concluded that the vaccine would be effective in preventing polio for all U.S. school children. consequently, it was made available for general use.

Study design Answered
babeeb0oL 2021-08-10

### In a study designed to investigate the effects of a strong magnetic field on the early development of mice, ten cages, each containing three 30-day-old albino female mice, were subjected for a period of 12 days to a magnetic field having an average strength of 80 Oe/cm. Thirty other mice, housed in ten similar cages, were not put in the magnetic field and served as controls. Listed in the table are the weight gains, in grams, for each of the twenty sets of mice. Test whether the variances of the two sets of weight gains are significantly different. Let α=0.05. For the mice in the magnetic field, ${s}_{X}=5.67$. for the other mice, ${s}_{Y}=3.18$

Study design Answered
foass77W 2021-07-04

### An experiment designed to study the relationship between hypertension and cigarette smoking yielded the following data. Test the hypothesis that whether or not an individual has hypertension is independent of how much that person smokes.

Study design Answered
coexpennan 2021-07-02

### Do piano lessons improve the spatial-temporal reasoning of preschool children? A study designed to investigate this question measured the spatial-temporal reasoning of a random sample of 34 preschool children before and after 6 months of piano lessons. The differences (After - Before) in the reasoning scores have mean 3.618 and standard deviation 3.055.

Study design Answered
glamrockqueen7 2021-06-24

### State whether the investigation in question is an observational study or a designed experiment. Justify your answer in each case. The National Association of Colleges and Employers (NACE) compiles information on salary offers to new college graduates and publishes the results in Salary Survey.

Study design Answered
waigaK 2021-06-24

### What are the treatments for a designed study that utilizes one qualitative factor with four levels: A, B, C, and D?

Study design Answered
Rui Baldwin 2021-06-22

### A bank wants to know which of two incentive plans will most increase the use of its credit cards. It offers each incentive to a group of current credit card customers, determined at random, and compares the amount charged during the following six months. What type of study design is being used to produce data?

Study design Answered
ka1leE 2021-06-20

### State whether the investigation in question is an observational study or a designed experiment. Justify your answer in each case.In the 1940s and early 1950s, the public was greatly concerned about polio. In an attempt to prevent this disease, Jonas Salk of the University of Pittsburgh developed a polio vaccine. In a test of the vaccine’s efficacy, involving nearly 2 million grade-school children, half of the children received the Salk vaccine; the other half received a placebo, in this case an injection of salt dissolved in water. Neither the children nor the doctors performing the diagnoses knew which children belonged to which group, but an evaluation center did. The center found that the incidence of polio was far less among the children inoculated with the Salk vaccine. From that information, the researchers concluded that the vaccine would be effective in preventing polio for all U.S. school children; consequently, it was made available for general use.

Study design Answered
Dolly Robinson 2021-06-20

### Define the following terms: a. Observational study, b. Designed experiment.

Study design Answered
Khaleesi Herbert 2021-06-18

### Who is more likely to binge drink—male or female college students? The Harvard School of Public Health surveys random samples of male and female undergraduates at four-year colleges and universities about whether they have engaged in binge drinking. What type of study design is being used to produce data?

Study design Answered
postillan4 2021-06-16

### Refer to the Journal of Experimental Social Psychology (Vol. 45, 2009) study of whether buying gifts truly buys love. Recall that study participants were randomly assigned to play the role of gift giver or gift receiver. Gift receivers were asked to provide the level of appreciation (measured on a 7-point scale where 1 = "not at all" and 7 = "to a great extent") they had for the last birthday gift they received from a loved one. Gift givers were asked to recall the last birthday gift they gave to a loved one and to provide the level of appreciation the loved one had for the gift. The researchers wanted to know if the average level of appreciation is higher for birthday gift givers than for birthday gift receivers. a. Why is this study designed? b. Specify the key elements of the study: experimental unit, response variable, factor, and treatments.

Study design Answered
permaneceerc 2021-06-15

### Determine whether the study is an observational study or an experiment. Explain. In a study designed to research the effect of music on driving habits, 1000 motorists ages 17- 25 years old were asked whether the music they listened to influenced their driving.

Contrary to popular belief, study design in terms of statistics and probability is not only used by engineers but also implemented by modern fashion designers and those specialists who produce and construct certain video games. As you will take a look at study design examples, you will see that it relates not only to probability and statistical analysis but to creative thinking as well, which makes it even more interesting. Start with your study design example and compare it to available study design questions as it will help you to deal with equations and choose the most efficient solutions.