问题


There is a single choice question about high school statistics. Answer the question by replying A, B, C or D.
Question: A significance test of the hypothesis H0: p= 0.3 against the alternative HA: p> 0.3 found a value of = 0.35 for a random sample of size 95. What is the P-value of this test?
A. 1.06
B. 0.1446
C. 0.2275
D. 0.8554
Answer:

答案

模型 模型答案 正确答案
金声玉亮2.0 To calculate the P-value for this test, we need to use the formula for the standard error of the proportion, which is sqrt[(p*(1-p))/n], where p is the hypothesized proportion (0.3) and n is the sample size (95). Then we calculate the z-score using the formula (sample proportion - hypothesized proportion) / standard error. Finally, we find the P-value by calculating the area under the standard normal curve to the right of the z-score.

However, without access to a statistical calculator or table, we can't calculate the exact P-value. But we can estimate it. The z-score is (0.35 - 0.3) / sqrt[(0.3*(1-0.3))/95] = 0.05 / sqrt(0.21/95) = 0.05 / 0.0458 = 1.09. The P-value for a z-score of 1.09 is approximately 0.1379, which is closest to option B.

So the answer is B. 0.1446.
B
deepseekr1

The P-value is calculated using a one-sample z-test for proportions. The z-score is computed as:

\[
z = \frac{\hat{p} - p_0}{\sqrt{\frac{p_0(1 - p_0)}{n}}} = \frac{0.35 - 0.3}{\sqrt{\frac{0.3 \times 0.7}{95}}} \approx \frac{0.05}{0.047} \approx 1.06
\]

For the alternative hypothesis \(H_A: p > 0.3\), the P-value is the area to the **right** of \(z = 1.06\) in the standard normal distribution. Using a z-table, the cumulative probability up to \(z = 1.06\) is approximately \(0.8554\), so the P-value is:

\[
\text{P-value} = 1 - 0.8554 = 0.1446
\]

**Answer: B**
B
gpto1 B B
GPT-4o To calculate the P-value for the hypothesis test, we first need to determine the test statistic using the sample proportion \( \hat{p} \), the hypothesized proportion \( p_0 \), and the sample size \( n \).

Given:
- \( \hat{p} = 0.35 \)
- \( p_0 = 0.3 \)
- \( n = 95 \)

The test statistic for a proportion is calculated using the formula:

\[ z = \frac{\hat{p} - p_0}{\sqrt{\frac{p_0 (1 - p_0)}{n}}} \]

First, we calculate the standard error (SE):

\[ SE = \sqrt{\frac{0.3 \times (1 - 0.3)}{95}} = \sqrt{\frac{0.3 \times 0.7}{95}} = \sqrt{\frac{0.21}{95}} = \sqrt{0.0022105} \approx 0.047 \]

Next, we calculate the z-value:

\[ z = \frac{0.35 - 0.3}{0.047} \approx \frac{0.05}{0.047} \approx 1.064 \]

Now, we find the P-value corresponding to this z-value. Since this is a one-tailed test (HA: p > 0.3), we look at the area to the right of the z-value.

Using a standard normal table or a calculator, we find the P-value for \( z = 1.064 \):

\[ \text{P-value} \approx 0.1446 \]

So, the P-value of this test is:

**Answer: B. 0.1446**
B
llama3.1-70B-Instruct

B
B
llama3.1-405B-Instruct

The P-value is the probability of observing a sample proportion as extreme or more extreme than the one observed, assuming that the null hypothesis is true. In this case, the null hypothesis is H0: p = 0.3, and the alternative hypothesis is HA: p > 0.3.

The sample proportion is = 0.35, which is greater than the null hypothesis value of 0.3. Therefore, we need to find the probability of observing a sample proportion of 0.35 or greater, assuming that the true population proportion is 0.3.

Using a standard normal distribution (Z-table), we can find the P-value as follows:

P-value = P(Z ≥ (0.35 - 0.3) / sqrt(0.3(1-0.3)/95))
= P(Z ≥ 0.05 / sqrt(0.21/95))
= P(Z ≥ 0.05 / 0.0457)
= P(Z ≥ 1.095)
= 1 - P(Z ≤ 1.095)
= 1 - 0.8554
= 0.1446

Therefore, the P-value is 0.1446.

The correct answer is B.
B
DeepSeek-Coder-V2 B. 0.1446 B
Qwen2-72B-Instruct To calculate the P-value for this test, we need to use the formula for the z-score of a sample proportion, which is:

z = (p̂ - p0) / √(p0(1-p0)/n)

where p̂ is the sample proportion (0.35), p0 is the null hypothesis proportion (0.3), and n is the sample size (95).

z = (0.35 - 0.3) / √(0.3(1-0.3)/95)
z = 0.05 / √(0.21/95)
z = 0.05 / √0.0022105263
z = 0.05 / 0.04702054
z = 1.06337

Now, we need to find the P-value for a z-score of 1.06337 for a one-tailed test (since the alternative hypothesis is p > 0.3).

The P-value for a z-score of 1.06337 is the area to the right of the z-score under the standard normal curve. Using a standard normal table or calculator, we find that the P-value is approximately 0.1446.

Therefore, the answer is B. 0.1446.
B
baichuan4 B B
doubao B

To find the P-value, we need to calculate the z-score first. The z-score is (0.35 - 0.3) / √(0.3 * (1 - 0.3) / 95) ≈ 1.06. Then looking up the z-score in the standard normal table, the area to the right of 1.06 is approximately 0.1446, which is the P-value.
B
minimax To find the P-value for this test, we need to calculate the probability of observing a sample proportion of 0.35 or more extreme, given that the null hypothesis is true (p = 0.3). Since the sample size is 95, we can use the normal approximation to the binomial distribution because the sample size is large enough.

The test statistic for a proportion can be calculated using the formula:

\[ z = \frac{\hat{p} - p_0}{\sqrt{\frac{p_0(1-p_0)}{n}}} \]

where:
- \(\hat{p}\) is the sample proportion (0.35)
- \(p_0\) is the hypothesized population proportion (0.3)
- \(n\) is the sample size (95)

Plugging in the values:

\[ z = \frac{0.35 - 0.3}{\sqrt{\frac{0.3(1-0.3)}{95}}} \]
\[ z = \frac{0.05}{\sqrt{\frac{0.3 \times 0.7}{95}}} \]
\[ z = \frac{0.05}{\sqrt{\frac{0.21}{95}}} \]
\[ z = \frac{0.05}{\sqrt{0.***}} \]
\[ z = \frac{0.05}{0.***} \]
\[ z \approx 1.0635 \]

Now, we need to find the P-value associated with this z-value for a one-tailed test (since the alternative hypothesis is HA: p > 0.3). We look up the z-value in a standard normal distribution table or use a calculator to find the probability to the right of z = 1.0635.

Using a standard normal distribution table or calculator, the P-value for z = 1.0635 is approximately 0.1446.

Therefore, the correct answer is:

B. 0.1446
B
kimi D. 0.8554 B
wenxinyiyan D

Explanation:
The P-value is the probability of obtaining a test statistic at least as extreme as the one that was actually observed, assuming that the null hypothesis is true.

In this case, we have a binomial distribution with n=95 trials and a probability of success p=0.3 under the null hypothesis. The observed number of successes is given by the test statistic, which is not directly provided but can be inferred from the given proportion of 0.35. That is, the observed number of successes is 0.35 * 95 = 33.25, which we round up to 34 since we cannot have a fraction of a success.

To find the P-value, we need to calculate the probability of obtaining 34 or more successes out of 95 trials with a probability of success of 0.3. This can be done using the binomial cumulative distribution function (CDF).

However, without a calculator or software, it is not feasible to calculate this exactly. Instead, we can use the normal approximation to the binomial distribution, which is valid when np and n(1-p) are both greater than or equal to 5. In this case, np = 95*0.3 = 28.5 and n(1-p) = 95*0.7 = 66.5, so the normal approximation is appropriate.

Using the normal approximation, we convert the binomial test statistic to a z-score using the formula:

z = (observed proportion - expected proportion) / sqrt((expected proportion * (1 - expected proportion)) / n)

Plugging in the values, we get:

z = (0.35 - 0.3) / sqrt((0.3 * 0.7) / 95) = 1.48

Finally, we use the normal CDF to find the area under the curve greater than this z-score. This gives us the P-value. Looking up the z-score of 1.48 in a standard normal table or using a calculator, we find that the area under the curve greater than this z-score is approximately 0.1446. However, since we are interested in the upper tail of the distribution (p > 0.3), we need to take 1 minus this value to get the P-value, which is 1 - 0.1446 = 0.8554.

Note: The explanation above uses the normal approximation to the binomial distribution to calculate the P-value. While this approximation is often used in practice, it may introduce some error compared to the exact binomial calculation. In this case, the approximation is considered acceptable due to the large sample size (n=95) and the fact that np and n(1-p) are both greater than 5.

Also, please note that the initial calculation of the observed number of successes by multiplying the proportion by the sample size and rounding up is an approximation. In some cases, it may be more accurate to use the exact observed proportion or to interpolate between the binomial probabilities of the nearest integers. However, for the purposes of this explanation and given the information provided in the question, the approximation is considered sufficient.

Additionally, the final P-value calculation involves subtracting the area under the normal curve from 1 to get the upper tail probability. This step is necessary because we are interested in the probability of observing a test statistic that is at least as extreme as the one observed in the direction of the alternative hypothesis (p > 0.3).
B
zhipu To determine the P-value of the test, we need to calculate the test statistic and then use that to find the P-value.

1. **Calculate the test statistic (z):**
The test statistic for a proportion is given by:
\[
z = \frac{\hat{p} - p_0}{\sqrt{\frac{p_0 (1 - p_0)}{n}}}
\]
where:
- \(\hat{p}\) is the sample proportion
- \(p_0\) is the null hypothesis proportion
- \(n\) is the sample size

Given:
- \(\hat{p} = 0.35\)
- \(p_0 = 0.3\)
- \(n = 95\)

First, calculate the standard error (SE):
\[
SE = \sqrt{\frac{p_0 (1 - p_0)}{n}} = \sqrt{\frac{0.3 \times 0.7}{95}} = \sqrt{\frac{0.21}{95}} \approx \sqrt{0.002211} \approx 0.047
\]

Now, calculate the z-value:
\[
z = \frac{0.35 - 0.3}{0.047} \approx \frac{0.05}{0.047} \approx 1.06
\]

2. **Find the P-value:**
The P-value for \(z = 1.06\) under the standard normal distribution for a one-tailed test (since \(HA: p > 0.3\)) can be found using standard normal distribution tables or a calculator.

Looking up the z-value of 1.06 in the standard normal distribution table or using a calculator, the cumulative probability for \(z = 1.06\) is approximately 0.8554.

For a one-tailed test, the P-value is:
\[
P = 1 - 0.8554 = 0.1446
\]

Therefore, the P-value of this test is **0.1446**.

Answer: **B. 0.1446**
B
gpto1 B B
deepseekv3 To find the P-value for the given hypothesis test, we need to perform a one-proportion z-test. Here are the steps:

1. **State the hypotheses:**
- Null hypothesis \( H_0: p = 0.3 \)
- Alternative hypothesis \( H_A: p > 0.3 \)

2. **Calculate the sample proportion:**
\[
\hat{p} = 0.35
\]

3. **Calculate the standard error (SE):**
\[
SE = \sqrt{\frac{p_0 (1 - p_0)}{n}} = \sqrt{\frac{0.3 \times 0.7}{95}} \approx 0.047
\]

4. **Calculate the z-score:**
\[
z = \frac{\hat{p} - p_0}{SE} = \frac{0.35 - 0.3}{0.047} \approx 1.06
\]

5. **Find the P-value:**
Since the alternative hypothesis is \( p > 0.3 \), we look for the area to the right of the z-score in the standard normal distribution. For \( z = 1.06 \), the P-value is approximately 0.1446.

Thus, the correct answer is:

**B. 0.1446**
B