Calculate P Value From Mean And Standard Error
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Contents 1. Input 2. Basic Data Types 3. Basic Operations and Numerical Descriptions 4. Basic Probability Distributions 5. Basic Plots 6. Intermediate calculate p value from mean and standard deviation online Plotting 7. Indexing Into Vectors 8. Linear Least Squares Regression 9. Calculating
Calculate P Value From Mean And Standard Deviation In Excel
Confidence Intervals 10. Calculating p Values 10.1. Calculating a Single p Value From a Normal Distribution 10.2. Calculating a
How To Calculate Standard Error Of The Mean Difference
Single p Value From a t Distribution 10.3. Calculating Many p Values From a t Distribution 10.4. The Easy Way 11. Calculating The Power Of A Test 12. Two Way Tables 13.
How To Calculate Standard Error Of The Mean In R
Data Management 14. Time Data Types 15. Introduction to Programming 16. Object Oriented Programming 17. Case Study: Working Through a HW Problem 18. Case Study II: A JAMA Paper on Cholesterol R Tutorial Docs » 10. Calculating p Values 10. Calculating p Values¶ Contents Calculating a Single p Value From a Normal Distribution Calculating a Single p Value From a t Distribution Calculating how to calculate standard error of the mean in excel 2010 Many p Values From a t Distribution The Easy Way Here we look at some examples of calculating p values. The examples are for both normal and t distributions. We assume that you can enter data and know the commands associated with basic probability. We first show how to do the calculations the hard way and show how to do the calculations. The last method makes use of the t.test command and demonstrates an easier way to calculate a p value. 10.1. Calculating a Single p Value From a Normal Distribution¶ We look at the steps necessary to calculate the p value for a particular test. In the interest of simplicity we only look at a two sided test, and we focus on one example. Here we want to show that the mean is not close to a fixed value, a. \[\begin{split}H_o: \mu_x & = & a,\end{split}\]\[\begin{split}H_a: \mu_x & \neq & a,\end{split}\] The p value is calculated for a particular sample mean. Here we assume that we obtained a sample mean, x and want to find its p value. It is the probability that we would
login Login Username * Password * Forgot your sign in details? Need to activate BMA members Sign in via OpenAthens Sign in via your institution Edition: US how to calculate standard error of the mean formula UK South Asia International Toggle navigation The BMJ logo Site map Search Search form how to calculate standard error of the mean in minitab SearchSearch Advanced search Search responses Search blogs Toggle top menu ResearchAt a glance Research papers Research methods and reporting Minerva how to calculate standard error of the mean in sas Research news EducationAt a glance Clinical reviews Practice Minerva Endgames State of the art News & ViewsAt a glance News Features Editorials Analysis Observations Head to head Editor's choice Letters Obituaries Views and reviews http://www.cyclismo.org/tutorial/R/pValues.html Rapid responses Campaigns Archive For authors Jobs Hosted Research How to obtain the P... How to obtain the P value from a confidence interval Research Methods & Reporting Statistics Notes How to obtain the P value from a confidence interval BMJ 2011; 343 doi: http://dx.doi.org/10.1136/bmj.d2304 (Published 08 August 2011) Cite this as: BMJ 2011;343:d2304 Article Related content Metrics Responses Peer review Douglas G Altman, professor of statistics in http://www.bmj.com/content/343/bmj.d2304 medicine 1, J Martin Bland, professor of health statistics21Centre for Statistics in Medicine, University of Oxford, Oxford OX2 6UD2Department of Health Sciences, University of York, Heslington, York YO10 5DDCorrespondence to: D G Altman doug.altman{at}csm.ox.ac.ukWe have shown in a previous Statistics Note1 how we can calculate a confidence interval (CI) from a P value. Some published articles report confidence intervals, but do not give corresponding P values. Here we show how a confidence interval can be used to calculate a P value, should this be required. This might also be useful when the P value is given only imprecisely (eg, as P<0.05). Wherever they can be calculated, we are advocates of confidence intervals as much more useful than P values, but we like to be helpful. The method is outlined in the box below in which we have distinguished two cases.Steps to obtain the P value from the CI for an estimate of effect (Est) (a) P from CI for a differenceIf the upper and lower limits of a 95% CI are u and l respectively: 1 calculate the standard error: SE = (u − l)/(2×1.96) 2 calculate the test statistic: z = Est/SE 3 calculate the P value2: P = exp(−0.717×z − 0.416
Tour Start here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site About Us Learn more about Stack Overflow the company Business Learn more about http://stats.stackexchange.com/questions/56182/how-to-back-calculate-change-from-baseline-from-a-p-value-for-a-paired-t-test hiring developers or posting ads with us Cross Validated Questions Tags Users Badges Unanswered Ask Question _ Cross Validated is a question and answer site for people interested in statistics, machine learning, data analysis, data mining, and data visualization. Join them; it only takes a minute: Sign up Here's how it works: Anybody can ask a question Anybody can answer The best answers are voted up and rise to the top How to back-calculate change from baseline from standard error a p-value for a paired t test up vote 4 down vote favorite I have a result from a study in a research paper which gives a mean/SD for 2 time points (pre & post treatment), and a p-value based on a paired-samples t-test. What I want to calculate is the SD of the change from pre to post. Is there any way I can back-calculate this using the p-value and mean/SD for each time point? Thanks in advance- how to calculate Julie r t-test sample-size excel share|improve this question asked Apr 15 '13 at 20:02 Julie 212 add a comment| 1 Answer 1 active oldest votes up vote 3 down vote This is possible, and relatively straightforward given that a paired t-test simplifies to a one-sample t-test of the differences where: $t = \frac{\delta}{se} $ where $se = \frac{s}{\sqrt{n}}$ where $\delta$ is the difference in means (equivalently, the mean difference), and $se$ is the standard error of the difference in means, and $s$ is the standard deviation of the difference (which is what you want). I think the standard deviations of the two timepoints are not needed for this particular solution. I'll just add here that this will only be a useful exercise if the p-value is reported in some detail (e.g. if just reported p < 0.01, then you'll only be able to get an upper bound on the value of the sample standard deviation: and also the rounding inherent in the initial summary statistics might have a big impact. But for getting a rough idea about their sample standard deviation, I think the following will suffice.) SOLUTION: For a given $t$ with $x$ degrees of freedom (df, here = sample size - 1), the original authors would have derived the p-value by examining the two-tailed t-distribution (most likely two-tailed, anyway). You need to reverse this last process: take the inverse of the two-tailed t-di