1.
A model is a simplification or approximation of reality and hence will not reflect all of reality.
Correct Answer
A. True
Explanation
The explanation for the correct answer is that a model is a representation of reality that is created by simplifying or approximating the complex and intricate details of the real world. Due to this simplification, a model cannot capture all aspects of reality and may overlook certain factors or details. Therefore, it is true that a model will not reflect all of reality.
2.
Which of the following is a purpose for modeling?
Correct Answer
C. Prediction
Explanation
Modeling is a process of creating a simplified representation of a real-world system or phenomenon. One of the purposes of modeling is prediction, where the model is used to forecast future outcomes or behaviors based on the available data and assumptions. By developing a model, we can analyze different scenarios and make informed decisions based on the predicted outcomes. Therefore, prediction is a valid purpose for modeling.
3.
An admissible model must be consistent with all the data points.
Correct Answer
A. True
Explanation
An admissible model must be consistent with all the data points because admissibility refers to the ability of a model to accurately represent the observed data. If a model is not consistent with all the data points, it means that it is not able to accurately capture the patterns and relationships present in the data. Therefore, for a model to be considered admissible, it must be able to explain and account for all the data points.
4.
The Poisson distribution is only meant for ____ integers.
Correct Answer
B. Positive
Explanation
The Poisson distribution is only meant for positive integers because it models the number of events that occur in a fixed interval of time or space. It assumes that the events occur independently and at a constant rate. Since the number of events cannot be negative or non-integer, the Poisson distribution is only applicable to positive integers.
5.
A statistical model is nonparametric if the parameter set ¶ is infinite dimensional.
Correct Answer
A. True
Explanation
A statistical model is considered nonparametric if the parameter set is infinite dimensional. This means that the model does not make any specific assumptions about the distribution or shape of the data, allowing for more flexibility in modeling complex relationships. Nonparametric models are often used when there is limited prior knowledge about the data or when the underlying distribution is unknown. Therefore, the statement "True" accurately reflects the definition of a nonparametric statistical model.
6.
Two statistical models are nested if the first model cannot be transformed into the second model...
Correct Answer
B. False
Explanation
The statement is false because nested statistical models refer to a situation where one model is a special case or a simplified version of another model. In this case, the first model can be transformed into the second model by adding or removing variables or constraints. Therefore, the correct answer is false.
7.
Which of the following set are nested distributions?
Correct Answer
D. Gaussian
Explanation
The set of distributions mentioned in the question consists of various types such as Vector, Mean, Base, and Gaussian. Among these, only the Gaussian distribution is a nested distribution. A nested distribution refers to a distribution that is a subset or a special case of another distribution. In this case, the Gaussian distribution is a nested distribution because it is a specific type of distribution that falls under the broader category of continuous probability distributions.
8.
We can nest a model by...
Correct Answer
D. None of the above
Explanation
The given options do not provide a valid explanation for nesting a model. Nesting a model refers to including one model within another model, typically for creating more complex or hierarchical structures. It does not involve moving parameters sideways, forward, or backward. Therefore, none of the given options correctly explain how to nest a model.
9.
What can we get from a modeling data distribution?
Correct Answer
A. Expected outcome
Explanation
From modeling data distribution, we can obtain the expected outcome. This means that by analyzing the data and creating a model, we can predict or estimate the most likely or average outcome. This can be useful in various fields such as statistics, finance, and machine learning, where understanding the distribution of data helps in making informed decisions and predictions.
10.
In a statistical model specified via mathematical equations, some of the variables do not have specific values, but instead have...
Correct Answer
C. Probability distributions
Explanation
In a statistical model specified via mathematical equations, some variables do not have specific values but instead have probability distributions. This means that the variables can take on different values with certain probabilities. Probability distributions provide information about the likelihood of different outcomes occurring, allowing for uncertainty to be incorporated into the model. By using probability distributions, statistical models can capture the variability and uncertainty inherent in real-world data.