1. Announcement:
05-10-2017
Views:
1,856
Page 2 of 54 First 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 52 ... Last
Threads 61 to 120 of 3193

# Forum: Statistical Research

Statistical theory and methodology. Mathematical statistics. Parametric inference. Nonparametric inference.

1. ### Sticky: Proof of the day

In this thread we post one (or more if you can't wait) proof a day. I'll start by proving the that V=\sigma^2(X'X)^{-1} in the linear...

• Replies: 14
• Views: 18,696
10-11-2014, 12:02 PM
1. ### one sample t-test alternative

Hello, I hope someone can help me, because I am getting crazy with this. Imagine the following scenario: I have several participants. Each...

• Replies: 13
• Views: 2,231
04-10-2014, 07:08 AM
2. ### item-scale correlation

Hi, When running an item-scale correlation, what does it mean when research have corrected for overlap? Is there a way to do this in SAS?

• Replies: 13
• Views: 4,943
10-21-2014, 12:19 PM
3. ### Correlation

I have a list of vehicle models and a number of costs associated with them. For example: Mazda 1000.50 euro Peugeot 2000.23 euro Mazda...

• Replies: 12
• Views: 2,857
12-04-2008, 09:32 AM
4. ### Optimal combination of conditions

I am looking to find an efficient process to determine the set of conditions that results in the optimal likelihood of accomplishing some task. ...

• Replies: 12
• Views: 4,379
02-06-2011, 02:55 PM
5. ### General vs Generalized Linear Models

While defending my thesis yesterday, this difference was pointed out. Surprised that there was actually a difference I wasn't aware of, I've looked...

• Replies: 12
• Views: 13,621
06-23-2015, 12:52 PM
6. ### Comparing distributions

I'm working on analyzing data for a prof for publication and have come to a situation that I am lacking confidence in and am coming here for help. ...

• Replies: 12
• Views: 3,932
05-21-2012, 10:28 AM
7. ### Analytic options with multi-level data?

Hello, I've been struggling with choosing an analytical approach to some multi-level data (3 level) I'm working with and wanted to get some fresh...

• Replies: 12
• Views: 2,881
01-31-2013, 01:15 PM
8. ### Random or fixed slope in hlm?

Hello, I am doing multilevel analysis and I am not sure whether I should include a random slope or not. The Wald test produces the following...

• Replies: 12
• Views: 12,123
08-19-2012, 03:27 PM
9. ### Limit of standard normal CDF(x) as x goes to ∞?

Let N:\mathbb{R} \to be the CDF of the standard normal density function. I want to evaluate: \lim_{b\to 0^+} N(\frac{a}{b}). Clearly this is...

• Replies: 12
• Views: 95,081
10-18-2012, 09:39 AM
10. ### Some help in selecting appropriate tests

Hi. I'm currently conducting some research which requires me to analyse change in scores on a 34 item self-report questionnaire. The questionnaire...

• Replies: 12
• Views: 2,001
08-26-2013, 02:50 PM
11. ### Can anyone explain Poisson regression for doing time trend?

It would be a big help if someone could give a practical example (by hand) how Poisson regression is used to calculate a time trend line, and...

• Replies: 12
• Views: 6,721
02-19-2014, 06:52 PM
12. ### Monte Carlo simulation: how many runs?

Hi, Most papers I read related to Monte Carlo (MC) simulation method say that there is no rule on the minimum number of runs required. However, in...

• Replies: 12
• Views: 6,085
BGM
04-07-2015, 06:21 AM
13. ### Power calculation with measurement error on Y

I'm trying to do a power calculation for a study I'm involved in, and I'm a bit stuck. The study is about textual cues of trust. We want to...

• Replies: 12
• Views: 3,636
11-01-2016, 07:02 PM
14. ### which statistical test to use - Observed difference in outcome is due to chance?

Hi, I have results from two very sensitive but different lab test trying to find pathogen in a patient sample. For some patients, results from two...

• Replies: 12
• Views: 3,672
11-06-2016, 08:07 PM
15. ### Repeated k-fold Cross-Validation

I saw this: "Any advices on practice? It depends on the data, but it's common to find examples cases 10 fold CV, plus repetition: 10 fold CV,...

• Replies: 12
• Views: 7,121
12-16-2016, 10:35 AM
16. ### Random Sampling - Missing Something Easy and I know it

Hello everyone, I was asked to look over some data that came across my desk and I was stumped as to why it came out the way that it did. So the...

• Replies: 12
• Views: 859
07-25-2017, 11:21 AM
17. ### Help Anova

hi everyone, I currently try to find an open source C/C++statistical library. Basically, I want to calculate the p and F value from oneway (or N...

• Replies: 11
• Views: 4,627
12-14-2005, 05:55 PM
18. ### Eigenvector for large matrices

Well, this is kind of a linear algebra question, but is used very often in statistics, so it seems applicable for this forum. My question is, does...

• Replies: 11
• Views: 7,021
07-01-2008, 01:58 PM
19. ### Random Variables and Correlation

I claim that if x is a normal distributed random variable, and y is a uniformly distributed random variable then x and y cannot have a correlation of...

• Replies: 11
• Views: 5,662
11-20-2008, 03:47 PM
20. ### Mle

Hi guys, I need advice regarding this question: The height of students at university is a random variable from the N(\mu,25) distribution. A...

• Replies: 11
• Views: 3,289
06-10-2010, 01:17 PM
21. ### Confused regarding Principal Component Analysis

Hi all, I have a scenario in which I was advised to use Principle Component Analysis but my knowledge of stats is fairly rudimentary so I am...

• Replies: 11
• Views: 3,281
09-13-2010, 08:34 PM
22. ### Modelling the yield from sports bets - Potentially using a mixture of distributions?

Hello all, A friend of mine asked me to analyze some data which comes from placing bets on sports. Having read quite a few threads and seeing how...

• Replies: 11
• Views: 5,545
04-01-2011, 03:35 PM
23. ### Choosing a test value for a one sample t-test

Hi all, I am trying to determine how best to test a hypothesis I have formulated. I am examining a new user interface that allows the user to...

• Replies: 11
• Views: 4,069
09-13-2011, 01:28 PM
24. ### Logistic regression question

Hi, I have a large data set (over 1 million cases) and I put in approximately 5 to 10 IV that are all categorical. I am not getting a...

• Replies: 11
• Views: 5,496
10-20-2011, 11:11 AM
25. ### differences between values a meaningful unit (I like cake too)

Alright I'm still working away on my problem of distance between different types of behavior. I can calculate distances between occurrences and spit...

• Replies: 11
• Views: 2,007
11-04-2012, 01:01 AM
26. ### Using a t test not giving me what I want

Good afternoon all, I'm writing a procedure to simply identify if 2 values are significantly different enough to update the procedure. As an...

• Replies: 11
• Views: 1,669
08-28-2013, 06:27 AM
27. ### Analysis of a matched case-control study

Please, i need help on my analysis. It is a 1-1 matched case-control studies. I am willing to pay for the guidance. My deadline is friday.

• Replies: 11
• Views: 2,799
01-27-2014, 10:17 AM
28. ### Small difference but still significant?

I hae sample size of 67 participants. They took a pre and post knowledge survey. The maximum score was 14 answers correct. I run a pair ttest. These...

• Replies: 11
• Views: 2,682
11-30-2014, 03:42 AM
29. ### help with Normality test?

Hi all! this is probably a simple question; however, my statistics skills got a bit rusty and I cannot find an appropriate solution on the...

• Replies: 11
• Views: 1,528
06-23-2015, 03:51 PM
30. ### Assumptions for mix design anova with covariates

Hello I Would like to nake a mix design (I HAVE TWO GROUPS -SICK AND HEALTHY), AND I made a cognitive measure of long / short exposure stimulus. ...

• Replies: 11
• Views: 2,488
01-01-2016, 01:36 PM
31. ### Theoretical Regression Problems

What is the term for when your outcome variable is truncated and that may be dampening your results? For example, you use a dichotomous outcome for...

• Replies: 11
• Views: 2,317
02-07-2017, 09:52 AM
32. ### Shapley Value

Hi, I'm trying to get a "Shapley Value" for determining each attributes utilities. I've already heard this could be done with simple excel or...

• Replies: 10
• Views: 13,162
09-28-2012, 09:44 AM
33. ### Which test to run (pretest-posttest)

Hi there! What is the best test to use to analyze data involving a pretest and posttest given to two different treatment groups? Thanks!

• Replies: 10
• Views: 7,518
02-11-2011, 10:46 PM
34. ### Which test to believe ?

Hi, I did some analysis, I had 1 scale variable and 1 grouping variable with 2 groups. I ran a t-test and got p value of 0.09. The distribution...

• Replies: 10
• Views: 4,345
07-16-2011, 02:04 AM
35. ### power analysis for parameter estimation of a gamma distribution?

How do I calculate the needed sample size to determine if the parameter estimates are accurate enough for a gamma distribution? Thanks.

• Replies: 10
• Views: 3,632
08-04-2011, 05:30 PM
36. ### Cramer's V effect size based on df

I saw a presentation about chi-square testing and correlations. Specifically calculating effect size for Cramer's V results. The puzzling thing was...

• Replies: 10
• Views: 26,722
10-15-2011, 12:41 PM
37. ### Transform data for outlier analysis?

Hey everyone, I have a data set which is log normally distributed and want to detect outliers, so far I used a threshold approach: vector...

• Replies: 10
• Views: 7,716
11-10-2011, 05:37 AM
38. ### alternative to anova

What is an alternative statistical test to anova. I have a large varience between three groups (control and two experimental). How can I determine...

• Replies: 10
• Views: 5,467
12-16-2011, 09:43 PM
39. ### T-test help with determining whether its 1 or 2 tailed?

Hi, I need to perform a t-test to determine the relationship between US govt spending on Police and the number of Rapes annually. So I have 53...

• Replies: 10
• Views: 7,119
02-28-2012, 02:31 PM
40. ### Reporting non-statistically significant t-test

If we assess that with alpha=.05 and beta=.8 we can evaluate the statistical power to detect effect sizes based on the sample. 783 participants are...

• Replies: 10
• Views: 11,708
02-24-2012, 03:33 PM
41. ### Variance sum law proof

Hey guys, I was wondering if something could get me started on a proof for the variance sum law. For the sake of clarification, I'm referring...

• Replies: 10
• Views: 11,233
03-17-2012, 10:10 PM
42. ### Using Mann-Whitney U?

Hi, I'm confused about which statistic to use. I want to find out if a law in two different states influences service delivery (get referral/ do...

• Replies: 10
• Views: 3,573
08-27-2012, 03:56 PM
43. ### Do you need to satisfy assumptions in regression if you do 10-fold cross-validation?

I wanted to get your opinion on this. When building models we want to make sure that the variables we have selected can be used in a model to predict...

• Replies: 10
• Views: 2,434
12-29-2012, 06:48 AM
44. ### 2 Sample T Test for Nonnormal data

Hi everyone! I work in the advertising industry and I am in the process of creating a t test calculator. The calculator will be used to test the...

• Replies: 10
• Views: 2,683
04-09-2013, 07:13 PM
45. ### Roulette- reducing variance

Hello gents. I am new here and I have a question. Is someone here has a bit of will and knowledge around some statistical software or programming...

• Replies: 10
• Views: 2,839
05-16-2013, 06:14 PM
46. ### [SOLVED] Recommendation: Journals that may have survey research

Hopefully the title says it all. I'm trying to get more familiar with survey research (how it's written up, research questions, methods of analysis...

• Replies: 10
• Views: 2,047
05-28-2013, 09:16 PM
47. ### p-values : binomial vs. normal

I've taken and tutor some basic statistics courses. What I've been taught is that to compute p-values (false positive rate) for hypothesis testing on...

• Replies: 10
• Views: 2,971
08-01-2013, 07:28 PM
48. ### I.I.D assumption of T-test

I am writing my second master's thesis now and I came across a situation where V\neq{V}. So I thought I'd test whether this need to be the case in...

• Replies: 10
• Views: 3,654
01-16-2014, 02:29 PM
49. ### Interpreting Kruskal-Wallis results

Hi all, I've just finished my undergrad thesis and the reviewers strongly recommended that I pursue formal publication of my results. I thought...

• Replies: 10
• Views: 4,545
08-03-2014, 04:53 PM
50. ### Nonparametric methods

If I have a sample with the size of the right and left arms of each of these people.So I have two dependent groups, since these are the same person,...

• Replies: 10
• Views: 2,497
12-16-2014, 06:30 AM

Page 2 of 54 First 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 52 ... Last

Use this control to limit the display of threads to those newer than the specified time frame.

Allows you to choose the data by which the thread list will be sorted.

Note: when sorting by date, 'descending order' will show the newest results first.