Assignment 2 T Test By Wednesday February 27, 2013 Post Your
Assignment 2 T Testbywednesday February 27 2013 Post Your Assignme
Calculate the “t” value for independent groups for the provided data using the formula from the module. Determine whether a statistically significant difference exists between female and male HR managers' salaries using the appropriate t-test. Develop a research question, a testable hypothesis, select a confidence level, and determine degrees of freedom. Report the critical t-values based on degrees of freedom. The response should be 2-3 pages, including all calculations, interpretations, and conclusions.
Paper For Above instruction
The purpose of this paper is to analyze whether there is a statistically significant difference between the salaries of female and male human resource (HR) managers using an independent samples t-test. This analysis involves constructing an appropriate research question, formulating a testable hypothesis, selecting a confidence level, calculating the t-value, identifying the degrees of freedom, and comparing the calculated t-value to the critical t-value to arrive at a conclusion.
Research Question and Hypotheses:
The primary research question posed is: "Is there a significant difference between the average salaries of female and male HR managers?" Based on this, the null hypothesis (H₀) states that there is no difference in salaries between female and male HR managers, symbolically: H₀: μ_female = μ_male. Conversely, the alternative hypothesis (H₁) posits that a difference exists: H₁: μ_female ≠ μ_male. This is a two-tailed test aimed at detecting any difference, regardless of direction.
Data and Descriptive Statistics:
The salary data are as follows:
- Female HR Directors: 50,000; 75,000; 72,000; 67,000; 54,000; 52,000; 68,000; 71,000; 55,000
- Male HR Directors: 58,000; 69,000; 73,000; 67,000; 55,000; 63,000; 53,000; 70,000; 69,000; 60,000
Calculating the means and standard deviations for each group provides foundational descriptive statistics. For females, the mean salary approximates to $61,800, while for males, the mean salary is around $63,500. These figures suggest potential similarity, but statistical testing is necessary to confirm.
Calculations:
Using the formula for the t-statistic for independent samples:
t = (mean₁ - mean₂) / √[(s₁²/n₁) + (s₂²/n₂)]
Where s₁ and s₂ are the standard deviations of each group, and n₁ and n₂ are the group sample sizes. Calculation of standard deviations yields s_female ≈ 8,600 and s_male ≈ 7,400. The sample sizes are n_female = 9 and n_male = 10.
Plugging in these values:
t = (61,800 - 63,500) / √[(8,600²/9) + (7,400²/10)] ≈ -1,700 / √[(82,960,000/9) + (54,760,000/10)] ≈ -1,700 / √[9,228,889 + 5,476,000] ≈ -1,700 / √[14,704,889] ≈ -1,700 / 3,837 ≈ -0.44
Degrees of Freedom and Critical Value:
Calculating degrees of freedom (df) using the Welch-Satterthwaite equation: df ≈ 17.4, approximated to 17 for table lookup. Using a 95% confidence level (α=0.05) for a two-tailed test, the critical t-value from t-distribution tables is approximately ±2.11.
Interpretation and Conclusion:
Since the calculated t-value of approximately -0.44 does not exceed the critical t-value of ±2.11, we fail to reject the null hypothesis. This indicates there is no statistically significant difference between the salaries of female and male HR managers at the 95% confidence level. The data support the conclusion that gender does not significantly influence HR manager salaries within this sample.
In summary, the independent samples t-test revealed no significant salary difference based on gender among HR managers. This outcome highlights the importance of empirical analysis over assumptions and underscores that observed numerical differences may not be statistically meaningful.
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