Which of the following statements is true concerning epidemic diseases? They are usually not very contagious. At the end of an epidemic, a disease spreads at an increasing rate and then abruptly disappears. They usually appear and disappear seasonally.
Which of the following statements are true concerning a triangular or recursive system?
Which of the following statements are true concerning a triangular or recursive system? Correct! (i), (ii) and (iii) are all correct. A triangular system is one where the causality between the “endogenous variables” all goes in one direction.
In which type of medical system is it assumed that illness is due to impersonal mechanistic causes in nature that can be potentially understood and cured by the application of the scientific method of discovery?
The naturalistic explanation assumes that illness is only due to impersonal, mechanistic causes in nature that can be potentially understood and cured by the application of the scientific method of discovery. Typical causes of illness accepted in naturalistic medical systems include: 1. 2.
Which of the following is the function of epidemiology?
Epidemiology includes assessment of the distribution (including describing demographic characteristics of an affected population), determinants (including a study of possible risk factors), and the application to control health problems (such as closing a restaurant).
Which of the following is correct concerning logit and probit models?
Response a is correct since the logit and probit models are similar in spirit: they both use a transformation of the model so that the estimated probabilities are bounded between zero and one – the only difference is the form of the transformation – a cumulative logistic for the logit model and a cumulative normal for …
Which one of the following is examined by looking at a goodness of fit statistic?
Which one of the following is examined by looking at a goodness of fit statistic? How well the population regression function fits the sample regression function. Correct! Goodness of fit statistics show how well the estimated model fits the data – that is – how well the sample regression function fits the data.
What is said when the errors are not independently distributed?
Error term observations are drawn independently (and therefore not correlated) from each other. When observed errors follow a pattern, they are said to be serially correlated or autocorrelated.
Which of the following is a violation of OLS assumptions?
Violations of this assumption can occur because there is simultaneity between the independent and dependent variables, omitted variable bias, or measurement error in the independent variables. Violating this assumption biases the coefficient estimate.
