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A certain city divides naturally into ten district neighborhoods. How might a real estate appraiser select a sample of singlefamily homes that could be used as a basis for developing an equation to predict appraised value from characteristics such as age, size, number of bathrooms, distance to the nearest school, and so on? Is the study enumerative or analytic?

Short Answer

Expert verified
Use stratified sampling across the neighborhoods; it's an analytic study.

Step by step solution

01

Identify the Sampling Technique

To select a sample of single-family homes from the ten district neighborhoods, a stratified sampling technique can be used. In stratified sampling, the population is divided into mutually exclusive groups, or 'strata,' that are naturally occurring, such as neighborhoods in this case. This ensures representation from each district.
02

Define Strata and Decide Sample Size

Define the 'strata' as the ten neighborhoods. Determine the sample size based on the total number of single-family homes in each neighborhood. You may wish to select an equal number of homes from each district or proportionate to the size of the neighborhood.
03

Random Selection Within Each Stratum

After determining how many homes to sample from each neighborhood, randomly select homes. This can be done using a random number generator or drawing lots from a list of all homes in each district.
04

Collect Data on Selected Sample

Gather data on the chosen homes regarding their characteristics, such as age, size, number of bathrooms, and distance to the nearest school. These characteristics will be used to form the predictive equation.
05

Determine the Nature of the Study

Evaluate whether the study is enumerative or analytic. An enumerative study makes inferences about the sample for descriptive purposes, while an analytic study aims to develop models or predictions for broader application. Since the goal is to develop a predictive equation, this study is considered analytic.

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Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Sampling Techniques
Sampling techniques are essential tools in research, especially when you cannot observe every individual in a population. In this exercise, we focus on a method called stratified sampling. Stratified sampling involves dividing the population into distinct subgroups, known as "strata." Each of these subgroups shares specific characteristics. For instance, in our scenario, the city is divided into ten distinct neighborhoods, each forming a separate stratum.

This technique helps in ensuring that every group is represented in the sample, providing more precise estimates than simple random sampling. This is especially useful in heterogeneous populations. After dividing the population, you decide on the size of the sample from each stratum, either equally or proportionately. Finally, homes are randomly selected within each subgroup for analysis. This method balances representation with randomness, ensuring a comprehensive and unbiased sample.
Analytical Study
An analytical study is focused on deriving insights that can be broadly applied, often using data to develop new models or theories. Unlike an enumerative study, which merely describes a sample, an analytical study inquires about deeper relationships. It aims to create solutions or predictions that extend beyond the observed data.

In the context of real estate appraisal, our objective is to derive a predictive model for home appraisals. By examining characteristics like age, size, and proximity to schools, we strive to understand how these factors influence property values. The results of such an analytical study are not limited to the homes examined but are used to predict values in broader contexts. This approach is critical when wanting to apply findings to larger populations or different scenarios.
Predictive Modeling
Predictive modeling is a powerful tool used to forecast outcomes based on data. It involves building mathematical or statistical models that can predict future events or trends from existing data. In the case of real estate appraisal, predictive modeling helps in estimating the value of homes based on various characteristics.

The model uses the collected data on features such as age, size, number of bathrooms, and distance to schools to predict the appraised value of homes. It often involves techniques like regression analysis where a formula is derived to express the relationships between these features and the property's value. Such models are validated and refined using part of the sample data to ensure accuracy. Predictive modeling is essential for making informed decisions in real estate, as it helps appraisers and buyers anticipate market trends.
Real Estate Appraisal
Real estate appraisal is the process of determining the value of a property, often for the purpose of sale, insurance, or taxation. Appraisers rely on various data points and methods to provide an objective estimate of a property's worth.

In this exercise, the appraiser aims to use characteristics like age, size, and location to determine a home's market value. These factors can significantly influence real estate prices due to their impact on demand and desirability. Appraisal is not just about knowing the current market but also understanding individual property traits that add or subtract value.

An accurate appraisal is crucial as it can affect financial transactions and decisions. By using systematic approaches like stratified sampling and predictive modeling, appraisers can enhance their estimates' reliability, making them valuable to buyers, sellers, and lenders alike.

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Most popular questions from this chapter

The article "Snow Cover and Temperature Relationships in North America and Eurasia" (J. Climate and Applied Meteorology, 1983: 460-469) used statistical techniques to relate the amount of snow cover on each continent to average continental temperature. Data presented there included the following ten observations on October snow cover for Eurasia during the years 1970-1979 (in million \(\mathrm{km}^{2}\) ): \(\begin{array}{llllllllll}6.5 & 12.0 & 14.9 & 10.0 & 10.7 & 7.9 & 21.9 & 12.5 & 14.5 & 9.2\end{array}\) What would you report as a representative, or typical, value of October snow cover for this period, and what prompted your choice?

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