Assignment 3: Inferential Statistics Analysis And Wri 167897
Assignment 3 Inferential Statistics Analysis And Writeupdwight Wall
Assignment #3 – Inferential Statistics Analysis and Writeup Dwight Wallace Class: STAT 200 Spring Instructor: Date: May 1, 2021
Part A – Inferential Statistics Data Plan Analysis
Introduction: I am 35 years old, married, have three children, and have a bachelor’s degree in business management and have a household income of $79,700, with $17,600 in housing expenses and $1,900 in electricity expenses. My focus is determining how marital status affects both housing and electricity expenses.
Table 1 – Variables Used for the Analysis
- Variable 1 – Marital status: Socioeconomic, married head of household, Qualitative
- Variable 2 – Electricity Expenses: Annual electricity expenses, Quantitative
- Variable 3 – Housing Expenses: Annual housing expenses, Quantitative
Data Analysis
Table 2: Confidence Interval Information and Results
- Variable - Housing: X = the annual expenses for housing; µ = the mean of housing expenses annually; Excel is used
- State and check the assumptions for confidence level and rationale for using it
a) Confidence Interval: Statistical Interpretation:
Table 3
Part B: Results Write Up
Two Sample Hypothesis Test Analysis: Discussion
Paper For Above instruction
The purpose of this statistical analysis is to evaluate the relationship between marital status and household expenses, specifically focusing on housing and electricity costs. The analysis employs inferential statistical methods, including confidence intervals and hypothesis tests, to determine whether marital status significantly influences these expenses. This paper provides a comprehensive approach, detailing the data plan, assumptions, analysis procedures, and interpretative discussion based on real or hypothetical data scenarios.
Introduction
Understanding the effect of socioeconomic factors such as marital status on household expenses offers valuable insights for policymakers, social scientists, and economists. The specific focus of this study is to assess whether being married influences the average annual housing and electricity expenses compared to other marital statuses. Given that household expenditures are vital indicators of economic stability and living standards, it is essential to analyze these relationships thoroughly. Utilizing inferential statistics allows for making valid generalizations from sample data to broader populations, which is crucial for informed decision-making and policy formulation.
Data Plan and Variables
The analysis begins with clear identification of the variables involved. Marital status is a qualitative (categorical) variable representing whether a respondent is married or unmarried. The economic impact is measured numerically via two quantitative variables: annual housing expenses and annual electricity expenses. Data collection should ensure a representative sample that captures various socioeconomic strata, ideally with sufficient size to perform statistically valid tests.
For this analysis, the key variables are:
- Marital status: categorized as married or unmarried (qualitative)
- Housing expenses: measured in dollars, continuous variable (quantitative)
- Electricity expenses: measured in dollars, continuous variable (quantitative)
By defining these variables precisely, the analysis can employ appropriate statistical tools such as confidence intervals for mean expenses and hypothesis testing to evaluate differences across groups.
Confidence Interval and Assumption Checks
Confidence intervals estimate the range within which the true population mean of a variable, such as housing expenses, likely falls. In this case, a 95% confidence level is typically used, implying that if the same population is sampled repeatedly, approximately 95% of the calculated intervals would contain the true mean.
Before conducting the analysis, certain assumptions must be verified:
- The sample data for housing expenses should be approximately normally distributed, especially for small sample sizes. This can be checked via histograms or normality tests such as Shapiro-Wilk.
- Independence of observations: each data point should be independent of others, which depends on the sampling method.
- Homogeneity of variances between groups (married versus unmarried) when comparing means, assessed via Levene’s test or F-test.
Confirming these assumptions ensures the validity of confidence intervals and hypothesis tests, guiding the choice of parametric or non-parametric methods as needed.
Analysis Procedure and Results
Assuming the data meet the necessary assumptions, the analysis proceeds with calculating confidence intervals for the mean housing expenses using sample data and standard formulas involving sample mean, standard deviation, and sample size. For example, the confidence interval is calculated as:
CI = sample mean ± (critical value) × (standard error)
where the critical value is derived from the t-distribution based on the degrees of freedom.
Similarly, hypothesis testing compares the mean expenses between married and unmarried groups to evaluate whether observed differences are statistically significant. The null hypothesis posits no difference in mean expenses based on marital status, while the alternative hypothesis suggests a difference exists. A t-test for independent samples is appropriate here.
Suppose the analysis indicates that married individuals tend to have higher housing expenses, with a statistically significant difference at the 0.05 significance level. This supports the notion that marital status influences household expenditure patterns. Conversely, if no significant difference is found, it suggests marital status may not be a determining factor for expenses in this context.
Discussion and Interpretation
The findings from the confidence intervals and hypothesis tests provide insights into the economic behaviors associated with marital status. For example, a higher average housing expense among married households could reflect increased family size, joint income sources, or different living arrangements. Understanding these patterns aids in economic planning and social policy development.
It is critical to interpret these results within the study’s limitations. Sample size, data quality, and assumption adherence substantially affect the reliability of inferred conclusions. Further research with larger, more diverse samples may be necessary to generalize results broadly.
Moreover, while this analysis focuses on marital status, other factors like income, education, or employment may confound the relationship. Multivariate analyses or regression modeling could better isolate the effect of marital status on expenses, controlling for these variables.
Conclusion
This inferential statistical analysis sheds light on the potential influence of marital status on household expenses, specifically housing and electricity costs. Employing confidence intervals and hypothesis testing within the framework of proper assumptions provides robust, interpretable results. These findings can contribute to targeted economic policies and inform individuals about expenditure patterns related to marital status.
References
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