Math Problem Statement
a popular theory is that presidential candidates have an advantage if they are taller than thier opponents presidents height = 176,186,176,186,193,170 hieght of main opponent 167,186,180,170,188,183 the null hypothesis is Ho=miud=0 the alternative is H1:miud > 0cm identify the T statistic and the p-value construct a confiden interval <miud<__ in this ecxample miud is the mean value of the difference d for the population of all pairs of data the difference have a mean greater than 0 and the significance interval is 0.01
Solution
We are conducting a one-sample t-test for paired data (dependent samples) to determine if the mean difference () in height between presidents and their main opponents is significantly greater than 0.
Step 1: Compute the Differences ()
The differences between the heights of the presidents and their main opponents are:
Presidents' Heights () | Opponents' Heights () | Difference () |
---|---|---|
176 | 167 | 9 |
186 | 186 | 0 |
176 | 180 | -4 |
186 | 170 | 16 |
193 | 188 | 5 |
170 | 183 | -13 |
The differences () are:
Step 2: Compute Sample Statistics
We compute:
- Mean of differences ()
- Standard deviation of differences ()
- Sample size ()
Let's calculate these values. numpy as np
Given differences
d = np.array([9, 0, -4, 16, 5, -13])
Compute mean and standard deviation
d_mean = np.mean(d) d_std = np.std(d, ddof=1) # Sample standard deviation (ddof=1 for unbiased estimate) n = len(d)
d_mean, d_std, nThe computed values are:
- Mean difference:
- Standard deviation:
- Sample size:
Step 3: Compute the T-Statistic
The t-statistic is given by:
Let's compute it. Compute t-statistic t_stat = d_mean / (d_std / np.sqrt(n)) t_statThe t-statistic is .
Step 4: Compute the p-value
Since this is a one-tailed test (), we compute:
Let's calculate the p-value. scipy.stats import t
Degrees of freedom
df = n - 1
Compute one-tailed p-value
p_value = 1 - t.cdf(t_stat, df) p_valueThe p-value is .
Step 5: Construct the Confidence Interval
The 99% confidence interval for is given by:
where is the critical value from the t-distribution with at a 99% confidence level.
Let's compute this interval. Get the critical t-value for 99% confidence level (two-tailed) t_critical = t.ppf(0.995, df) # 0.995 because it's two-tailed
Compute margin of error
margin_error = t_critical * (d_std / np.sqrt(n))
Compute confidence interval
lower_bound = d_mean - margin_error upper_bound = d_mean + margin_error
lower_bound, upper_boundIt seems like I can’t do more advanced data analysis right now. Please try again later.
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Math Problem Analysis
Mathematical Concepts
Inferential Statistics
Hypothesis Testing
Paired Sample t-Test
Confidence Intervals
Formulas
Mean of Differences: ȳd = (Σd) / n
Standard Deviation of Differences: sd = sqrt[(Σ(d - ȳd)²) / (n-1)]
T-Statistic: t = (ȳd - μ0) / (sd / sqrt(n))
Confidence Interval: ȳd ± t* × (sd / sqrt(n))
Theorems
Student's t-distribution
Central Limit Theorem
Suitable Grade Level
Undergraduate Statistics, Advanced High School AP Statistics
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