Research questions on qualitative study and utilizing observational data collection methodology.How dies witnessing domestic violence in childhood impact a person becoming criminal in adulthood? Qualitative data to be collected. From the records of the criminals how much of domestic violence in childhood was there in their childhood and the gravity of the crimes committed by the criminals in adulthood are to be collected:Once the entire data is collected, Association of Attributes can be carried out to find out how much witnessing domestic violence in childhood impact a person becoming criminal in adulthood

base on the above research question can you answer the following below:

1.what would you like to learn about the sample? what type of sampling and behaviors would you use or observe?

2. what type of data would you have at the end of your research study and how might you analyse it to answer your research question? how would you generate data from your sample?

Assume that SAT scores are normally distributed with a mean of 1000 and a standard deviation of 150. Use this information to answer the following questions. Round final answers to the nearest whole number.

What is the lowest SAT score that can be in the top 10% of testers?

What is the highest SAT score that can be in the bottom 5% of testers?

Between which two SAT scores do the middle 50% of testers lie?

In a recent year, Delaware had the highest per capita annual income with $51,803. Assume that σ = $4,850. A random sample of 39 state residents were selected.

What is the distribution of the sample mean income?

What is the probability that the sample mean income is greater than $50,800?

A developmental psychologist is studying cognitive functions in children. Three-, four-, and five-year-olds are asked to choose between one large cookie or three smaller cookies that add up to only about half the mass of the large cookie. The number of children choosing each alternative is shown for each age group below:

  
What is the p value that corresponds to the chi-square statistic for these data?

Suppose that the data for a chi-square test are as shown in the table below:

  
What is the p value that corresponds to the chi-square statistic for these data?

A researcher believes she has found a gene that is associated with having panic attacks. Ten out of her 15 panic patients have the gene, whereas only 5 out of 25 control subjects have the gene. What is the value of the chi-square statistic she should use to test the association between the suspected gene and the tendency to have panic attacks?

Researchers investigating temperament in dogs have a database of reactivity scores from a population of N = 1000 puppies.  The reactivity scores are normally distributed with a mean of mu = 175 and a standard deviation of sigma = 20; higher scores indicate higher reactivity (that is, the puppy is more likely to become aroused by novel stimuli).

Dr. Kobe is also conducting temperament testing, but his local shelter is much smaller than Dr. Santos’.  Thus, he is only able to obtain a sample size of n = 20 puppies.

a. What is the likelihood that Dr. Kobe will obtain a mean reactivity score of 168 or lower?

b. What is the likelihood that Dr. Kobe will obtain a mean reactivity score of 190 or higher?

c. Why should the probability of obtaining a sample mean less than M = 165 be larger for Dr. Kobe than Dr. Santos?

1. (5 pts) You are going to roll a pair of dice 108 times and record the sum of each roll. Before beginning, make a prediction about how you think the sums will be distributed. (Each sum will occur equally often, there will be more 12s than any other sum, there will be more 5s than any other sum, etc.) Record your prediction here:

2. (5 pts) Roll the dice 108 times and record the sum of each roll in the table provided below.

3. (22 pts) Find the experimental probability of rolling each sum. Fill out the following table:

4. (5 pts) Compare your outcomes to your prediction. Was your prediction correct? Why do you think this happened?

5. (5 pts) What number(s) occurred most often? Least often? Why do you think that is?

1. In 2007 the mean property crime rate (per 100,000) people for the 24 states west of the Mississippi River was 3331; the standard deviation was 729. Assume the distribution of crime rate is unimodal and symmetric.

A). The bottom 16% of the property crime rates are less than what value?

B) The top 2.5% of the property crime rates are greater than what value?

C) What percent of property crime rates are between 3391 and 5518?

1. Researchers have noted a decline in cognitive functioning as people age (Bartus, 1990). However, the results from other research suggests that the antioxidants in foods such as blueberries can reduce and even reverse these age-related declines, at least in laboratory rats (Joseph et al., 1999). Based on these results, one might theorize that the same antioxidants might also benefit elderly humans. Suppose a researcher is interested in testing this theory. The researcher obtains a sample of n = 16 adults who are older than 65, and gives each participant a daily dose of a blueberry supplement that is very high in antioxidants. After taking the supplement for 6 months, the participants are given a standardized cognitive skills test and produce M = 54. For the general population of elderly adults, scores on the test average μ = 50 and form a normal distribution with σ = 12.

Do the data from this sample provide evidence that the blueberry supplement increases cognitive skills among elderly people? Using a one-tail test with α = .05.

a. State the null hypothesis in words and in a statistical form.

b. State the alternative hypothesis in words and a statistical form.

c. Compute the appropriate statistic to test the hypotheses. Sketch the distribution with the standard error and locate the critical region with the critical value

d. State your statistical decision. (.5)

e. Compute Cohen’s d to measure the size of the effect. Interpret what this effect size

really means in this context.

f. What is your conclusion? (don't forget the statistical information).

g. Given your statistical decision (in part d), what type of decision error could you have made

{Exercise 3.29 (Algorithmic)}

The results of a national survey showed that on average, adults sleep 6.9 hours per night. Suppose that the standard deviation is 1 hours.

Round your answers to the nearest whole number.

1. Use Chebyshev's theorem to calculate the percentage of individuals who sleep between 4.9 and 8.9 hours.
   At least %
   
2. Use Chebyshev's theorem to calculate the percentage of individuals who sleep between 3.9 and 9.9 hours.
   At least %
   
3. Assume that the number of hours of sleep follows a bell-shaped distribution. Use the empirical rule to calculate the percentage of individuals who sleep between 4.9 and 8.9 hours per day.
   %
   
   How does this result compare to the value that you obtained using Chebyshev's theorem in part (a)?
   SelectThe empirical rule produces a larger percentage than Chebyshev's theoremChebyshev's theorem produces a larger percentage than the empirical ruleBoth methods produce the same percentage

Question 1

The travel agency Paradise Retreats has developed a model to predict the price per night of holiday apartment rentals in the coast of Croatia:

?=550+11?1−5?2

?: price of the apartment per night (in kunas)

?1: area of the apartment (in square meters)

?2: distance to the beach (in km)

According to Paradise Retreats’ model:

How much more expensive (in kunas) will be the rental of a 60 square-meter apartment on the beachfront compared with a 60 square-meter apartment 10 km from the beach?

Introduce your answer as a positive number.

How much will the price per night decrease when the area of the apartment decreases by 20 square meters?

Introduce your answer as a positive number.

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Question 2

The summary output of Paradise Retreats' model in Excel is in the tables below:

According to the tables, which of the following statements about this regression model are true?

A) This regression model explains less than 60% of the variation of the price per night.

B) The area of the apartment is not significant at a confidence level of 95%.

C) The area of the apartment is not significant at a confidence level of 99%.

D) The area of the apartment is significant at a confidence level of 99%.

E) The distance to the beach is not significant at a confidence level of 99%.

F) None of the above.

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Question 3

Paradise Retreats offer a wide range of options for an unforgettable holiday in Croatia. Their portfolio includes apartments on the coast and cabins in the mountains. On average, their customers book many more apartments than cabins every month. Paradise Retreats analyzed some historical data, did a chi-squared test and confirmed that the number of apartments booked every month follows a normal distribution with an average of 23 and a standard deviation of 7.

What is the probability that more than 29 apartments are booked through Paradise Retreats in a month?

Write your answer not as a percentage, but as a decimal number with 4 decimal places (e.g. if the probability is 87.56%, write 0.8756 in the answer box).

What is the probability that less than 21 apartments are booked through Paradise Retreats in a month?

Write your answer not as a percentage, but as a decimal number with 4 decimal places (e.g. if the probability is 87.56%, write 0.8756 in the answer box).

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Question 4

The number of mountain cabins that are booked through Paradise Retreats every month follows a Poisson distribution with a mean of 4. At Paradise Retreats, they are considering to reduce the number of cabins included in their portfolio.

What is the probability that at least one cabin is booked through Paradise Retreats in any given month?

Write your answer not as a percentage, but as a decimal number with 4 decimal places (e.g. if the probability is 87.56%, write 0.8756 in the answer box).

If Paradise Retreats only has 3 cabins available for rent, what is the probability of not meeting the demand for cabins during a given month?

Write your answer not as a percentage, but as a decimal number with 4 decimal places (e.g. if the probability is 87.56%, write 0.8756 in the answer box).

A food safety guideline is that the mercury in fish should be below 1 part per million​ (ppm). Listed below are the amounts of mercury​ (ppm) found in tuna sushi sampled at different stores in a major city. Construct a 99​% confidence interval estimate of the mean amount of mercury in the population.  0.59  0.80  0.10  0.89  1.33  0.51  0.84

   What is the confidence interval estimate of the population mean mu​? ? ppm < u < ? ppm

Does it appear that there is too much mercury in tuna​ sushi?

A.​Yes, because it is possible that the mean is not greater than 1 ppm.​ Also, at least one of the sample values exceeds 1​ ppm, so at least some of the fish have too much mercury.

B.​No, because it is not possible that the mean is greater than 1 ppm.​ Also, at least one of the sample values is less than 1​ ppm, so at least some of the fish are safe.

C.​No, because it is possible that the mean is not greater than 1 ppm.​ Also, at least one of the sample values is less than 1​ ppm, so at least some of the fish are safe.

D.​Yes, because it is possible that the mean is greater than 1 ppm.​ Also, at least one of the sample values exceeds 1​ ppm, so at least some of the fish have too much mercury.

Chapter 7

Correlation

7.1. Does correlation show causality? Why or why not?

7.2. For a Pearson Correlation, show what a perfect relationship looks like on a graph.

7.3. When do you use Pearson’s correlation and when do you use Spearman’s correlation? Kendall’s tau correlation?

7.4. Describe the difference between a biserial correlation and a point-biserial correlation.

Health insurers are beginning to offer telemedicine services online that replace the common office visit. A company provides a video service that allows subscribers to connect with a physician online and receive prescribed treatments. The company claims that users of its online service saved a significant amount of money on a typical visit. The data shown below ($), for a sample of 20 online doctor visits, are consistent with the savings per visit reported by the company.

Assuming the population is roughly symmetric, construct a 95% confidence interval for the mean savings in dollars for a televisit to the doctor as opposed to an office visit. (Round your answers to the nearest cent.)

$  to $

3.    You would like to estimate the proportion of student loan debts that are in default. You randomly select 211 people who have student loans and find that 25 are in default.

A.    Construct a 95% confidence interval to estimate the proportion of student loans that are in default. (Round your sample proportion to 4 decimal points as well as round your margin of error to 4 decimal points. For example, .23916 would be .2392 and this represents 23.92%. State the answer as an interval – for example, 27.36% to 31.43%).

B.    Using the same confidence level, you would like the margin of error to be with 3%, how many people with student loans should you sample?