Questions and Answers of Environmental And Health Risk

Develop a definition of sustainable development that includes a list of what you consider to be the relevant factors in sustainable development. Assume that you are developing that definition for a
What do you understand to be the principal differences between cost- effectiveness and risk-cost-benefit analysis? Use approximately 600 words and give an example of each from your own work,
Discuss your understanding of probabilistic conditioning and critically assess its importance in practical decision making. using no more than 400 words.
Provide simple examples of different scales of measurement that can be used in environmental management.
In no more than 400 words, exemplify an environmental law case that deals with an environmental pollution problem using cost-benefit analysis. Please use an example from your own jurisdiction and
How does Learned Hand's test address uncertainty? Does this legal test address the variability about the magnitude of the loss? If you think it does not, suggest a simple way by which it can do so.
Suppose that the interest rate is 10%, for a public project that generates the following stream of annual net benefits: $12,000, $14,000, $10,000. $13,000, $22,000 and $30,000. Calculate the PDV of
In no more than 600 words, discuss the discount rate in terms of individual preferences for postponing consumption today for a later period. What assumptions would have to be made to justify a
Consider the cost/benefit ratio, namely (Total Benefits, in )/(Total Costs, in ). One alternative is discounted at an interest rate of 3%; another is discounted at 10%. Develop your own example using
Consider and describe the variability of B and C, as two random variables. How would you express that variability in calculating the difference (B-C)? Do you always reach the same conclusion about
Consider the B/C ratio to rank alternatives. How would you express the variability of the ratio? Do you think that the ranking reached with B and C as deterministic numbers (without variability) is
Consider the statement: Time series models are descriptive; therefore, the researcher must use other models to develop causal associations. Do you agree? Discuss your answer using statistical
Why are time series useful to the environmental manager, relative to other regression models such as the multiple regressions, in assessing the risks of diseases characterized by long periods of
Consider the assertion Cox's Proportional Hazards Model (PH) can be used to assess survivorship functions. Sketch an argument that supports this assertion and justify it. What would be an important
Poisson and logistic regression models can use independent variables that depend on time. In other words: X can be replaced by X(t). What is the benefit of accounting for time explicitly? Use
Suppose that there is some literature to guide the selection of dependent (response) and independent variables (exposure and others) as well as the selection of the form (linear or non-linear) of the
Suppose that you can use a simple model of exposure and response but that you can specify a more complicated model based on the physics of your problem. The more complicated model includes more
The time series analyses use autocorrelations and partial autocorrelations functions; their confidence intervals and other information having to do with goodness-of-fit. You fit an ARIMA (1,1,1) to
Why should determining the size of the sample take place before the sample is taken? What aspects of this determination would you consider in developing your answer? Can you set up a simple set of
Consider the basis of the hit theory of cancer. Suppose that a normal cell needs two hits from the carcinogen before it is irreversibly damaged and becomes cancerous. Write the appropriate expression
Discuss the differences, if any, between hormesis and thresholds. Limit your discussion to 400 words.
Do you think that probabilistic hit-related models are less biologically credible than models that use transition rates between stages and account for cell growth and death? Limit your answer to 600
Suppose that conceptually different types of models fit the experimental data very well. On what basis would you extrapolate downward to a region in which the extra risk is about 1*10? What would an
Suppose that you are working for your country's environmental agency. The administrator of that agency asks you to use either the LOEL/NOAEL approach or the dose-response models to set a tolerable
What are the fundamental biological differences, if any, between the multistage and the MVK models and why are those differences important? Use about 400 words.
Why should the BMD approach not be applicable to human carcinogens? Answer this question in 300 words or less, discussing both sides of the views.
Let the distribution of individual thresholds be log-normal. The dose- response is Pr(d) = a+ϕ[b+c*ln(d)], in which ϕ is the standardized cumulative normal probability density function and d is
Discuss the reasons why hormetic mechanism should be accounted for generally, as opposed to be accounted for in specific cases, in regulatory policy-making.
The issue is as follows. If we can generalize hormesis, like we generalize linear, non-threshold cancer dose response for regulatory risk assessment, what is the benefit to society for adopting this
Develop a formal way to represent the uncertainty in the choice of one default, relative to another. That is, assume that a linear and a non-linear model are biologically plausible, given the current
How can any regulatory choice of a causal argument be generalized? Take an exposure-response model of your choice. Suppose that its parameters have been estimated from data in a population of pigmies
Compare and contrast the Monte Carlo method with the bootstrap suggesting at least two important differences.
What might be the effect of deleting censored observation from the sample, and then using only the complete subset of observations on the accuracy of estimating the mean and the standard deviation of
Why should a risk assessor be concerned with propagating the uncertainty in the independent variables to describe the variability of the dependent variable in a formula?
Why does a network provide useful insights in modeling the relationship between exposure to air pollution and adverse response? Use less than 400 words.
In American Trucking Associations et al. v. Christine Todd Whitman (U.S. Supreme Court 99-1426), Section 108 (National Ambient Air Quality Standards) and Section 109 (a) of the Clean Air Act were
Develop a simple regression model based on Bayesian Network of the air pollution example developed in this chapter from the work of Ricci and Hughes (2000).
Are there difference between the regression approach in CART and the regression models discussed in Chapter 4? Discuss and provide simple examples of the differences and similarities with less than
Having to deal with empirical causation requires understanding the way in which nodes and linkages form. A question that may be considered is: What is the usefulness of developing nodes and linkages
Consider CART for regression. Sketch a CART model solution of exposure-response, using DEATH RATE, SO, PM2, PM10, AGE and RACE as the variables.
Sketch a Bayesian Network of exposure-response, using DEATH RATE. SO2. PM25. PM10. AGE and RACE. Are there any differences between CART and BN? Please discuss those differences as well as
Suppose that the data set is: X = 1.7, 1.9, 2.0, 2.1, 2.2, 2.4; Y = 1.9, 2.0, 2.1, 2.4; Z=1.7, 2.0, 2.0, 2.1, 2.2. Do not worry about the units of these data. How would you compare the population
Discuss the key differences between meta-analysis and pooling of data from samples. Illustrate your discussion with two examples using hypothetical data for pooling and literature results from a risk
Discuss and illustrate why the homogeneity of the variance is an important consideration in analyzing data. Use data from the literature or data in this chapter. Use about 300 words.
Discuss Bartlett's test and exemplify its application using n = 13 and s = 2.5, n2 = 7 and sz = 3.2; and n3 = 9 and s = 6.90, using 200 words.
Discuss some of the reasons for using exact tests relative to tests based on asymptotic (large sample) approximations (no more than 300 words), using risk management as your point of departure for
What is the difference between a regression model and the ANOVA, if any? Use any appropriate statistics textbooks, if needed, to answer this question. Use about 200 words.
Can meta-analysis account for the power of the meta-analysis study? What key aspects would be important to doing such power analysis and what implications would it have for the risk manager? Answer
Consider the 2*2 cross tabulation in whicha, b, c and are counts associated with two random variables: Label the random variables and complete the table. What does pr(For Accept) measure? What does
How would independence between random variables X and Y be determined? Develop a formula to determine if two random variables are independent. (Hint, if a random variable does not probabilistically
Consider the following table: How would you calculate the agreement due to chance and the actual agreement? Apply Cohen's to fully analyze this table (we used this table earlier). Disease No Disease
Discuss a way in which a correlation may be causal. Develop your own example, based on data that is available from your workplace. In the absence of data, refer to a subject you are interested in
How can Hill's criteria be related through simple correlations? Give two examples of your own making and use two hypothetical 2*2 contingency tables using your own data.
Consider the following data: X = 3, 10, 7, 6, 13, 9, 12, 15, 9.Y = 0.01, 0.13, 0.04, 0.16, 0.54, 0.15, 0.32, 0.21, 0.37 Assume that the data is ordinal. Select the test that is appropriate to study
Discuss the relevance of causal diagrams in the context of developing a conjecture about a mechanism that can lead to a hormetic response in humans; show your development of the appropriate causal
How would you calculate the RBSL for inhalation by residents near a site emitting benzene, using acceptable lifetime individual risk levels of 1/10,000 and 1/100,000? What is the implication of these
How would you develop a simple probabilistic model rather than using pre- established values, to describe the variability in the RBSL's calculated using the ASTM formulae?
The following table that depicts the number of accidents associated with Systems A and B:Develop the cumulative frequency distributions for A and B. Plot these distributions. What qualitative
Draw two risk curves (cumulative complements of the distributions for X and Y) in which System X is only partially less risky than System Y. How would you practically show the uncertainty about each
What is the key implication of the exponential model of the diffusion of the disease? Should there be a term in this model that accounts for saturation and for decline of the incidence numbers? If
Suppose that r = 1.Calculate the negative binomial probability of the random variable X for pr = 0.5 and n = 10.
Calculate the sample mean, median, mode and the sample CV (CV = mean/variance) for the data (in ppm): 10, 15, 20, 35, 50, 65, 120, 130, 145, 155, 1.235, and 1,800. Suppose that the value 1,800 is
Making a practical decision can involve many variables and relations. Some suggest that making decisions using scenarios (for example, selecting one or more outlying values, calculating the output
Develop a two-branches decision tree, starting with the single decision of having to travel home from a distance of 50 km. Use at least two chance nodes and two branches after these nodes. Express
Why is money not the best measure of value when dealing with risky events? Limit your answer to 400 words or less and use an example of your own making.
Could you develop a probabilistic version of a two-person game? Where would you place the probability numbers? Develop a suitable table and show your work; use your own numbers.
Provide a critique of utility theory in the context of catastrophic outcomes associated with the release of large amounts of air pollutants in a small area. Limit your answer to 400 words or less.
How can one be sure that all of the attributes of a choice are known? What can be done to obtain a full enumeration of the attributes? Assuming that you can enumerate the attributes relevant to a
Anand (2002) proposes a non-probabilistic representation of a decision problem when probabilities are absent. He uses Laplace's Principle of Insufficient Reason that assigns equal likelihoods to each