# P-Value Uncovered: Discover the Secrets with Plainmath's Expert Help

Recent questions in P-Value
Ariana Montgomery2022-07-19

## in a certain population, body weights are normally distributed with a mean of 152 pounds and a standard deviation of 26 pounds. how many people must be surveyed if we want to estimate the percentage who weigh more than 180 pounds? assume that we want 96% confidence that the error is no more than 4 percentage points

Ariana Montgomery2022-07-19

## find the point estimate of the proportion of people who wear hearing aids if in a random sample of 898 people, 46 people had hearing aids

College StatisticsOpen question
Punith Craźzz2022-07-11
Lorena Beard 2022-07-10

## Let $X\sim Binomial\left(n,p\right)$$H+0:p\ge .5$${H}_{1}:p<.5$How do we evaluate the p-value?ie. $P\left(X\ge x\mid p>=.5\right)$I have seen settings where this is just interpreted as $P\left(X\ge x\mid p=.5\right)$, but I'm not sure how this is the same thing.

slijmigrd 2022-07-08

## In the hypotehses testing, I would like to see an intuition how the operator $min$ and the constant $2$ in the computation of $p$-value of a two side alternative $p=2min\left(F\left({T}_{0}\right),1-F\left({T}_{0}\right)\right)$ can be derived and understood for a statistics ${T}_{0}$. Here $F$ is the c.d.f.

College StatisticsOpen question
Raghavendra Maila2022-07-07

## Resolve F_1 and F_2 into components along the u and v axes and determine the magnitude of these components

slijmigrd 2022-07-07

## I am trying to create an algorithm that could calculate the p-value given the chi-square statistic and the degrees of freedom. Can anyone please point me in the right direction on how I could go about to evaluate the formula and what prerequisites I need to learn before I could do it.

rmd1228887e 2022-07-06

## A representative of a potential supplier claims that at least 90% of the equipment manufactured and sold by the company has no defects. You have obtained a sample of equipment usage records from a firm that uses these machines. Of 121 machines in the records, 105 machines have no recorded defects. What is the probability of this event if the supplier’s claim is correct (i.e. The p -value). On the basis of this data, do you believe the representative’s claim?My thoughts:The significance level of the test: α = 0.1 (10%)The percentage of 121 machines that have no recorded defects is 86.7%.I am not sure how to arrive at the p-value from this data.

Carly Cannon 2022-07-04

## How do I calculate the $p$ value of the following?Students' height is approximately normal with s.d = $4$ inches, sample = $10$,mean height = $68$ inches.Calculate the $p$ value corresponding to the following null hypotheses.${H}_{0}$ = Avg. height is $70$ inches${H}_{1}$ = Avg. height is not $70$ inches

Sam Hardin 2022-07-01

## A poll from a previous year showed that $10\mathrm{%}$ of smartphone owners relied on their data plan as their primary form of internet access. Researchers were curious if that had changed, so they tested ${H}_{0}:p=10\mathrm{%}$ versus ${H}_{a}:p\ne 10\mathrm{%}$ where p is the proportion of smartphone owners who rely on their data plan as their primary form of internet access. They surveyed a random sample of $500$ smartphone owners and found that $13\mathrm{%}$ of them relied on their data plan.The test statistic for these results was $z\approx 2.236$, and the corresponding $P$-value was approximately $0.025$.Assuming the conditions for inference were met, which of these is an appropriate conclusion?a) At the $\alpha =0.01$ significance level, they should conclude that the proportion has changed from $10\mathrm{%}$.b) At the $\alpha =0.01$ significance level, they should conclude that the proportion is still $10\mathrm{%}$.c) At the $\alpha =0.05$ significance level, they should conclude that the proportion has changed from $10\mathrm{%}$.d) At the $\alpha =0.05$ significance level, they should conclude that the proportion is still $10\mathrm{%}$.The correct answer is $c$ but why could it not have been $b$? Why is it $c$?

Manteo2h 2022-06-26

## Intend to calculate the first and third quartiles of a lognormal distribution with mu and sigma (two lognormal parameters) equal to -0.33217492 and 0.6065058. The expected value and the standard deviation gave me 0.8622153003153145 and 0.6191622375133721.I intend to calculate the first and third quartiles and found this formula:to calculate the quartiles but I didn't quite understand how to apply it and how to calculate the p-value. How can I find out the first and third quartiles of this distribution?

migongoniwt 2022-06-25

## Calculation of $p$-value: Fabric water properties, ${H}_{0}:\mu \le 55\mathrm{%}$ versus ${H}_{A}:\mu >55\mathrm{%}$;$n=15,\overline{x}=59.81\mathrm{%},s=4.94\mathrm{%}$I understand that the hypothesized mean is $55$ samples mean is $59.81$ sample standard deviation is $4.94$ sample size is $15$. And I use the $t$-test, I have gotten $3.77106$. In this circumstance, how can I get the $p$-value, and what is different between critical value and $p$-value?

Dania Mueller 2022-06-24

## The summary of that regression shows that one of my variable has a big p-value (0.705). Should I include that variable when writing the the y hat equation?

abbracciopj 2022-06-24

## Suppose that for every α∈(0,1) we have a size α test with rejection region Rα. Then,$\text{p-value}=inf\left\{\alpha :T\left({X}^{n}\right)\in {R}_{\alpha }\right\}$That is, the p-value is the smallest level at which we can reject ${H}_{0}$.what is this exponent $n$. What does ${X}^{n}$ mean?

gledanju0 2022-06-24

## ${X}_{i}\sim Bern\left(p\right)$, $Y=\sum _{i=1}^{N}{X}_{i}$ and ${H}_{0}:p\ge 0.5$ vs ${H}_{1}:p<0.5$ with $\alpha =0.05$.I have to find the $p$-value at $n=30$ and $y=5$.I'm not sure if this correct, but I figured the $p$-value was simply:$P\left(Y\le 5\right)=\sum _{i=1}^{5}\left(\genfrac{}{}{0}{}{30}{y}\right)\left(0.5{\right)}^{y}\left(0.5{\right)}^{30-y}$which works out to be $0.00016$.If this is correct, then why have I been given $\alpha$?

kokoszzm 2022-06-22

## Suppose a coin with probability $p$ of heads is repeatedly flipped until $10$ heads appear. Call this number $X$. Find the p-value of ${H}_{0}:p=0.5$ versus the alternate ${H}_{a}:p\ne 0.5$ using the test statistic $|X-20|$ if $X=27$.

Ezekiel Yoder 2022-06-20