Statistiques
Analyse de données, distributions de probabilités et tests d'hypothèses.
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a survey asked, how many tattoos do you currently have on your body? of…
A. There is 90% confidence that the difference of the proportions is in the interval. Conclude that there is insufficient evidence of a significant difference in the proportion of…
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a survey asked, \how many tattoos do you currently have on your body?\ …
The lower bound is $-0.011$ The upper bound is $0.039$
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in october 1947, the gallup organization surveyed 1100 adults and asked…
B. Reject \(H_{0}\). There is sufficient evidence at the \(\alpha = 0.05\) level of significance to suggest the proportion of adults who totally abstain from alcohol has changed.
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in october 1947, the gallup organization surveyed 1100 adults and asked…
If the population proportions are equal, one would expect a sample difference proportion greater than or equal to the one observed in about 1 out of 1000 repetitions of this exper…
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in october 1947, the gallup organization surveyed 1100 adults and asked…
The P - value is $0.001$
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in october 1947, the gallup organization surveyed 1100 adults and asked…
\(3.18\)
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in october 1947, the gallup organization surveyed 1100 adults and asked…
$H_0:p_1 = p_2$; $H_1:p_1 eq p_2$
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in october 1947, the gallup organization surveyed 1100 adults and asked…
B. \(n_1\hat{p}_1(1-\hat{p}_1)\geq10\) and \(n_2\hat{p}_2(1 - \hat{p}_2)\geq10\), C. The samples are independent, E. The sample size is less than \(5\%\) of the population size fo…
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in october 1947, the gallup organization surveyed 1100 adults and asked…
The proportions are \(0.370\) and \(0.300\)
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in randomized, double - blind clinical trials of a new vaccine, infants…
A. Reject $H_0$. There is sufficient evidence to conclude that a higher proportion of subjects in group 1 experienced fever as a side effect than subjects in group 2 at the $\alph…
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in randomized, double-blind clinical trials of a new vaccine, infants w…
If the population proportions are equal one would expect a sample difference proportion greater than or equal to the one observed in about 15 out of 1000 repetitions of this exper…
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in randomized, double - blind clinical trials of a new vaccine, infants…
$0.015$
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in randomized, double - blind clinical trials of a new vaccine, infants…
\(2.16\)
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what to the slave is the fourth of july? an address delivered in roches…
Douglass's speech proclaims that the treatment of Black people directly contradicts the Declaration of Independence.
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in randomized, double - blind clinical trials of a new vaccine, infants…
- Model requirements: B, C, F - \(H_0:p_1 = p_2\), \(H_1:p_1>p_2\)
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in randomized, double - blind clinical trials of a new vaccine, infants…
B. \(n_1\hat{p}_1(1-\hat{p}_1)\geq10\) and \(n_2\hat{p}_2(1 - \hat{p}_2)\geq10\), C. The sample size is less than 5% of the population size for each sample, F. The samples are ind…
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construct a confidence interval for $p_1 - p_2$ at the given level of c…
The researchers are $95\%$ confident the difference between the two population proportions, $p_1 - p_2$, is between $-0.045$ and $0.063$.
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conduct a test at the $\\alpha = 0.10$ level of significance by determi…
C. Reject the null hypothesis because there is sufficient evidence to conclude that \(p_1 > p_2\)
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conduct a test at the \\( \\alpha = 0.10 \\) level of significance by d…
\(0.063\)
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conduct a test at the \\( \\alpha = 0.10 \\) level of significance by d…
\(z_0\approx1.53\)
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conduct a test at the \\( \\alpha = 0.10 \\) level of significance by d…
$z_{0}\approx1.52$
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conduct a test at the $alpha = 0.10$ level of significance by determini…
A. \(H_0:p_1 = p_2\) versus \(H_1:p_1>p_2\)
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determine whether the following sampling method is dependent or indepen…
- Sampling method: B. The sampling is independent because an individual selected for one sample does not dictate which individual is to be in the second sample. - Response variabl…
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determine whether the following sampling method is dependent or indepen…
For the sampling method: B. The sampling is independent because an individual selected for one sample does not dictate which individual is to be in the second sample. For the resp…
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complete the sentence below a sampling method is ____ when the individu…
dependent
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a sampling method is when an individual selected for one sample does no…
independent
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read the excerpt from julius caesar, act 2, scene 1. decius. shall no m…
Mark Antony's life will be spared because he will be useless without Caesar.
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explain the difference between statistical significance and practical s…
C. Statistical significance means that the sample statistic is not likely to come from the population whose parameter is stated in the null hypothesis. Practical significance refe…
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one year, the mean age of an inmate on death row was 40.1 years. a soci…
C. Since the mean age from the earlier year is contained in the interval, there is not sufficient evidence to conclude that the mean age had changed.
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one year, the mean age of an inmate on death row was 40.1 years. a soci…
With 95% confidence, the mean age of a death - row inmate is between \(34.95\) years and \(41.65\) years.
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one year, the mean age of an inmate on death row was 40.1 years. a soci…
\(H_0:\mu = 40.1\) and \(H_1:\mu eq40.1\)
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to test ( h_{0}: mu = 37 ) versus ( h_{1}: mu eq 37 ), a simple random …
The lower bound is \(36.933\). The upper bound is \(43.667\). Because the value \(37\) lies within the confidence interval, we fail to reject the null hypothesis.
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to test ( h_{0}: mu = 37 ) versus ( h_{1}: mu eq 37 ), a simple random …
(a) C. No—since the sample size is at least 30, the underlying population does not need to be normally distributed. (b) \(t_{0}\approx2.67\) (c) Because the P - value is greater t…
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calcium is essential to tree growth. in 1990, the concentration of calc…
Since \(P-\text{value}> \alpha\), we fail to reject the null hypothesis and conclude that there is not sufficient evidence that the calcium level in rainwater has changed.
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calcium is essential to tree growth. in 1990, the concentration of calc…
\(0.386\)
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calcium is essential to tree growth. in 1990, the concentration of calc…
\(t_{0}=0.92\)
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calcium is essential to tree growth. in 1990, the concentration of calc…
\(H_0:\mu = 0.11\) \(H_1:\mu eq0.11\)
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read the excerpt from act 2, scene 1, of julius caesar. casca. let us n…
Casca firmly reverses his position about including Cicero, as if he hadn't been the one to suggest it in the first place. Casca thinks he is making important decisions when Brutus…
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it has long been stated that the mean temperature of humans is 98.6°f. …
D. Reject \(H_0\) since the P - value is less than the significance level.
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it has long been stated that the mean temperature of humans is 98.6°f. …
\(0.000\)
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it has long been stated that the mean temperature of humans is 98.6°f. …
\(-4.74\)
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it has long been stated that the mean temperature of humans is 98.6°f. …
\(H_0:\mu = 98.6^{\circ}F\) and \(H_1:\mu<98.6^{\circ}F\)
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a credit score is used by credit agencies (such as mortgage companies a…
Fail to reject the null hypothesis. There is not sufficient evidence to claim that the mean credit score of high - income individuals is greater than \(708.8\).
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a credit score is used by credit agencies (such as mortgage companies a…
\(P-\text{value}\approx0.072\)
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a credit score is used by credit agencies (such as mortgage companies a…
\(t_0 = 1.50\)
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a credit score is used by credit agencies (such as mortgage companies a…
\(H_0:\mu = 708.8\) \(H_1:\mu>708.8\)
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in a study, researchers wanted to measure the effect of alcohol on the …
Reject the null hypothesis. There is sufficient evidence to claim that the mean hippocampal volume is less than \(9.02\mathrm{cm}^3\).
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in a study, researchers wanted to measure the effect of alcohol on the …
The P - value is approximately \(0.000\)
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in a study, researchers wanted to measure the effect of alcohol on the …
\(t_0=-4.87\)
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in a study, researchers wanted to measure the effect of alcohol on the …
\(H_{0}:\mu = 9.02\), \(H_{1}:\mu<9.02\)
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a college entrance exam company determined that a score of 24 on the ma…
Reject the null hypothesis and claim that there is sufficient evidence to conclude that the population mean is greater than 24.
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a college entrance exam company determined that a score of 24 on the ma…
\(0.006\)
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a college entrance exam company determined that a score of 24 on the ma…
\(t_{0}\approx2.56\)
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a college entrance exam company determined that a score of 24 on the ma…
- a) \(H_0:\mu = 24\) versus \(H_1:\mu>24\) - b) B. The students were randomly sampled; C. The sample size is larger than 30; E. The students' test scores were independent of one …
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a college entrance exam company determined that a score of 24 on the ma…
The appropriate null and alternative hypotheses are \(H_0:\mu = 24\) versus \(H_1:\mu>24\).
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several years ago, the mean height of women 20 years of age or older wa…
A. Do not reject the null hypothesis. There is not sufficient evidence to conclude that the mean height of women 20 years of age or older is greater today.
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several years ago, the mean height of women 20 years of age or older wa…
- (a) D. \(H_0:\mu = 63.7\) in versus \(H_1:\mu>63.7\) in - (b) A. There is a \(0.13\) probability of obtaining a sample mean height of \(64.1\) inches or taller from a population…
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several years ago, the mean height of women 20 years of age or older wa…
D. \(H_0:\mu = 63.7\) in versus \(H_1:\mu>63.7\) in
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consider the following hypotheses and sample data, and then complete pa…
Critical value: \(1.383\) \(t_{0}=1.31\) Conclusion: A. Do not reject \(H_{0}\). There is not sufficient evidence to conclude that \(\mu>17\) \(p-\text{value}=0.111\)
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consider the hypotheses below $h_0: \\mu = 50$ $h_1: \\mu \ eq 50$ give…
- Critical values: \(- 2.861,2.861\) - Test statistic \(t_{0}\approx3.91\) - A. Reject the null hypothesis. The data provide sufficient evidence to conclude that the mean differs …
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as arlette walks through a shopping mall, she happens to pass an older …
fail to notice the older woman's problem.
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consider the hypotheses below $h_0: \\mu = 60$ $h_1: \\mu < 60$ given t…
The p - value is \(0.002\) (rounded to three decimal places).
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consider the hypotheses below $h_0: \\mu = 60$ $h_1: \\mu < 60$ given t…
- The critical value is \(-1.311\) - The test statistic \(t_0=-3.08\) - The conclusion is B. Reject \(H_0\). There is sufficient evidence to conclude that \(\mu\lt60\)
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complete parts (a) through (c) below. (a) determine the critical value(…
(a) \(1.372\)
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complete parts (a) through (c) below (a) determine the critical value(s…
(a) \(1.330\) (b) \(-2.539\) (c) \(\pm3.012\)
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several magazines were grouped into three categories based on what leve…
\(H_0:\mu_{High}=\mu_{Medium}=\mu_{Low}\), \(H_a:\) At least one \(\mu_i\) is different. \(F = 23.89\) \(p - value\approx0.0000\) Since \(p - value<0.05\), reject \(H_0\) At the \…
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a) anova is an inferential method used for comparing select an answer a…
a) means b) all means are equal.
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2. which sentence describes how a words nuance affects reader connotati…
It creates a more negative or more positive feeling.
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hailey, a researcher at the davis institute for criminal justice, is co…
a. \(H_{0}\): The distribution of plea deals arranged by court - appointed attorneys is the same as the distribution of plea deals arranged by privately - retained attorneys. \(H_…
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migraine and acupuncture: a migraine is a particularly painful type of …
a) \(H_{0}\): Migraine pain relief is independent on receiving acupuncture. b) Treatment - Pain Free: Yes: \(12.5316\), Treatment - Pain Free: No: \(55.4684\), Control - Pain Free…
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the correlation between temperature and the likelihood that major leagu…
positive.
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you are conducting a test of homogeneity for the claim that two differe…
Expected values: |Category|Population #1|Population #2| |---|---|---| |A|25.995|53.005| |B|47.005|95.995| \(\chi^{2}=0.359\) \(P - \text{value}=0.5493\) We cannot conclude that at…
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a survey found that the american family generates an average of 17.2 po…
\( 0.6687 \)
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a survey found that the american family generates an average of 17.2 po…
\(0.3921\)
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problems 9 - 10: a bicycle travels 21 meters in 3 seconds. 9. complete …
| Time (sec) | Distance (m) | |----|----| | 3 | 21 | | \(1\frac{1}{2}\) | \(10.5\) | | \(0.9\) | \(6\frac{3}{10}\) | The constant of proportionality is \(7\), which represents the…
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isabel is a young student trying to buy a new car. she does not have a …
First dropdown: cosigner. Second dropdown: she is legally obligated to repay the loan.
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a bag is filled with 10 cubes. 7 cubes are green, and 3 cubes are pink.…
\(0.625\)
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a bag is filled with 10 cubes. 7 cubes are green, and 3 cubes are pink.…
\(\frac{7}{10}\)
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a bag is filled with 10 cubes. 8 cubes are pink, and 2 cubes are blue. …
\(\frac{4}{5}\)
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smokers are interested in the relationship between cigarette smoking an…
(b) \(0.32\) (c) \(0.34\) (d) \(0.4375\)
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three machines - a, b, and c - are used to produce a large quantity of …
(b) \(0.19\) (c) \(0.211\)
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(b) whats the probability that the part is defective? (round to 2 decim…
(b) \(0.02\) (rounded to 2 decimal places) (c) \(0.652\) (rounded to 3 decimal places)
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three machines - a, b, and c - are used to produce a large quantity of …
(b) \(0.21\) (c) \(0.286\)
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each of the 6 cats in a pet store was weighed. here are their weights (…
(a) Mean: $11.5$ pounds (b) Median: $13$ pounds
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suppose you are a researcher in a hospital. you are experimenting with …
$(2.3603,2.7731)$
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suppose you are a researcher in a hospital. you are experimenting with …
a) \(2.6111\) b) The population from which the sample is drawn must be approximately normally distributed. c) \((2.4054,2.8168)\)
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if the sample size is 13, then you cant say anything about the sampling…
$\mu_{\bar{x}} = 17$ $\sigma_{\bar{x}}\approx0.84$
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a random variable is not normally distributed, but it is mound shaped. …
- For the first multiple - choice question: If the sample size is 13, then you can't say anything about the sampling distribution of the sample mean, since the population of the r…
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a random variable is not normally distributed, but it is mound shaped. …
- First multiple - choice: If the sample size is 13, then you can't say anything about the sampling distribution of the sample mean, since the population of the random variable is…
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the total of individual weights of garbage discarded by 20 households i…
\(24.8450<\mu<34.3550\)
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given degree of freedom df = 5, find the probability by using the stude…
\(0.424\)
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scores for a common standardized college aptitude test are normally dis…
a) \(0.2514\) b) \(0.0062\) c) Yes. The probability indicates that it is (highly?) unlikely that by chance, a randomly selected group of students would get a mean as high as \(582…
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out of a sample of 100 adults aged 18 to 30, 34 still lived with their …
$0.2471<p<0.4329$
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a 2011 gallup survey based on telephone and face - to - face interviews…
We are 95% confident that 28% to 32% of all Chinese adults smoke.
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which of the following would result in the narrowest confidence interva…
A sample size of 100 with 95% confidence.
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a large fast - food restaurant is having a promotional game where game …
a) \(0.2174\) b) \(0.1557\) c) \(0.1528\)
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suppose that the distance of fly balls hit to the outfield (in baseball…
a) \(P(\text{fewer than }204\text{ feet})\approx15.4\%\) b) \(P(\text{more than }216\text{ feet})\approx78.5\%\)
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for a standard normal distribution, use your calculator to find: p(z < …
\(0.2206\)
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a student was asked to find a 98% confidence interval for the proportio…
With 98% confidence, the proportion of all students who take notes is between 0.12 and 0.28.
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question 15 all else equal, an increase in sample size will cause a(n) …
decrease