1. Announcement:
05-10-2017
Views:
1,776
Page 19 of 294 First 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 69 119 ... Last
Threads 1081 to 1140 of 17583

# Forum: Statistics

Statistics course and homework discussion. Elementary statistics.

1. ### Sticky: Forum Guidelines: Smart posting behavior pays off

Welcome to talkstats.com, the place for statistics help. This is a guideline for people who want to ask a question on this forum and value a...

• Replies: 1
• Views: 196,558
07-16-2014, 11:01 AM
2. ### Sticky: We only provide homework help to those who show effort

Welcome to Talk Stats Forum. In order to keep homework help effective and efficient, we request all members to abide by these guidelines: 1)...

• Replies: 0
• Views: 66,617
09-30-2005, 09:44 AM
1. ### treatment and control variables?

I am using an on-line effect size calculator and it asks for the M and SD of the treatment and control variables. Is treatment another term for...

• Replies: 1
• Views: 7,595
02-21-2009, 10:14 AM
2. ### Uniform Distribution Problem(s)

I just spent at least an hour and confused myself more than anything on the problem below. Upon using the formula f(x)=1/b-a you get 1/10 (.1). For...

• Replies: 4
• Views: 7,594
BGM
10-19-2011, 11:29 PM
3. ### Average of Averages?

This is as much a philosphical question as it is a stats question. I am analyzing some cleaning evolutions. Each cleaning evolution has a final cost....

• Replies: 1
• Views: 7,594
12-29-2011, 04:01 PM
4. ### Absence of interaction. Planned comparisons.

Hi, I'm doing data analysis for one of my experiments. The design of the experiment is 2 (word frequency) x 3 (phrase type). Both main effects (word...

• Replies: 6
• Views: 7,589
05-15-2008, 03:31 AM
5. ### Confidence Interval

A nutrition researcher wants to determine the mean fat content of hen’s eggs. She collects a sample of 40 eggs. She calculates a mean fat content...

• Replies: 1
• Views: 7,582
10-27-2007, 08:18 PM
6. ### A question about determining significance

Hi guys I'm trying to compare the differences in the results of a fitness test done by two different methods (and performed on a sample group of...

• Replies: 16
• Views: 7,554
05-12-2010, 03:10 AM
7. ### Kurtosis - where does the minus 3 come from?

I've been trawling the web for an example for quite a while. I understand that the 3 corrects the kurtosis of the normal distribution - I'm just not...

• Replies: 2
• Views: 7,552
12-22-2010, 07:34 PM
8. ### Determining if a distribution is normal

I'm trying to create a confidence interval, but I'm missing the fact of whether or not I'm given a normal distribution. If I'm given the mean, sample...

• Replies: 3
• Views: 7,551
10-18-2009, 02:28 PM
9. ### Statistics Question; Lottery: Buying 2 tickets is doubling your chances

Statement: You double your chances of winning the lottery by purchasing 2 tickets versus only purchasing 1 ticket. True or False? Provide your...

• Replies: 1
• Views: 7,551
12-04-2010, 05:47 PM
10. ### Inverse of the Standard Normal Cumulative Distribution Calculation

Hi Everyone, I'm trying to verify the calculation for the Inverse Cumulative Standard Normal Distribution Function represented by the Excel...

• Replies: 8
• Views: 7,551
10-02-2014, 10:39 AM
11. ### 50$$to the person who can help me answer 3 questions. willing to paypal 50$$\$ to the person who can help me answer 3 questions. :) 1, The mean weight of 9 randomly selected 5 years old boys babies...

• Replies: 31
• Views: 7,527
02-08-2012, 08:55 AM
12. ### How do I find the probability of the complement of B?

New here... How do I find the probability of the complement of B? Here is the full question: If B is the event of a child having brown hair,...

• Replies: 2
• Views: 7,521
02-15-2012, 02:57 AM
13. ### URGENT! Bartlett's Test and Mann's Test in Excel

Hi All, I would like to take my data in an excel spreadsheet, and test it with Bartlett's Test and Mann's Test. However, when I used...

• Replies: 0
• Views: 7,520
03-02-2010, 12:16 AM
14. ### z-score help

Find the z-score for having area 0.07 to its right under the standard normal curve, that is, find z 0.07. I have the choices of 1.45, 1.26, 1.48,...

• Replies: 1
• Views: 7,519
06-25-2010, 12:53 AM
15. ### Two-sample t confidence interval

Am I correct??!! Corn yields (bushels per acre) for experimental plots controlled to have 1 weed per meter of row and 3 weeds per meter of row: ...

• Replies: 2
• Views: 7,517
12-04-2005, 12:26 PM
16. ### Normal Distribution question for College Statistics?

Okay my college professor is an idiot and didn't teach this at all and he is going to put this on a test, so here is my question.... Steel Rods...

• Replies: 1
• Views: 7,515
10-21-2011, 05:47 AM
17. ### Help? testing assumptions

A garden center wants to store left-over packets of vegetable seeds for sale the following spring, but the center is concerned that the seeds may not...

• Replies: 1
• Views: 7,512
03-29-2011, 12:11 AM
18. ### Marginal Effect

Hi all, I'm studying business statistics and I'm just struggling to work out this problem. I have an equation (i think the study is universal)...

• Replies: 1
• Views: 7,511
05-18-2008, 05:05 PM
19. ### Nonparametric tests to support parametric tests

hi people, i am new here so excuse my 'innocence' in statistics. I was wondering if someone could tell me if i am on the right track. In my...

• Replies: 3
• Views: 7,503
06-21-2006, 11:00 PM
20. ### Unequal sample sizes in ANOVA/MANOVA analyses

Hi there. I am critiquing a study and I have realised that there are unequal sample sizes in their treatment and control groups. Some analyses...

• Replies: 0
• Views: 7,499
09-22-2010, 04:49 AM
21. ### Estimation and Confidence Intervals

I am Posting this for my wife who is in a Statistics class and has been doing very well up to this point. She has read the chapters 3 times and still...

• Replies: 2
• Views: 7,496
04-19-2010, 08:31 AM
22. ### How to determine significant differences in sample size of test & control groups

Hello, It's been quite a few years since college statistics, so I apologize in advance if this is a very novice question for this forum, I just...

• Replies: 1
• Views: 7,493
12-16-2009, 03:05 PM
23. ### Autocorrelation in the residuals

I understand what autocorrelation is and I understand what the residuals are, but what are the implications of having autocorrelated residuals? Does...

• Replies: 3
• Views: 7,486
06-11-2011, 01:22 AM
24. ### pearson;s or spearman correlation??

if i want to do correlation between two variables, both continues, as far as i understand if they are normly distributed , i will choose...

• Replies: 3
• Views: 7,483
09-16-2010, 08:31 AM
25. ### Percentiles

I am struggling with this question for my homework. Values: 13 13 13 20 26 27 31 34 34 34 35 35 36 37 38 41 41 41 45 47 47 47 50 51 53 54 56 62...

• Replies: 1
• Views: 7,483
09-01-2011, 12:24 PM
26. ### Kaplan Meier curve for recurrent event data

Hi, Can anyone help. I would like to do Kaplan Meier curves for some recurrent event data i.e. each patient has multiple events. Can I use a Kaplan...

• Replies: 2
• Views: 7,481
11-07-2010, 07:37 AM
27. ### relationship btwn main effects, interaction, simple effects

Hello, I took a graduate level stats course a few years ago (psychology department), but I am now realizing that there were some things I did not...

• Replies: 0
• Views: 7,478
07-05-2010, 12:14 AM
28. ### Advice on an average math student going to grad school for statistics

Greetings, I ran into this forum when trying to look for some nice probably problems.I found out this is a really cool place to talk about stats, so...

• Replies: 2
• Views: 7,476
12-11-2008, 04:40 PM
29. ### multiple linear regression: negative Y ?!

So I have my equation and it looks weird. The intercept is a small positive value and a lot of the co-efficients have large negative values. So that...

• Replies: 17
• Views: 7,468
02-22-2012, 01:27 PM
30. ### gamma distribution

Show that the sum of n independent identically distributed exponential random variables with parameter theta has a gamma distribution and give its...

• Replies: 1
• Views: 7,466
11-05-2006, 05:29 PM
31. ### Normal and Standard normal distributed variable

What is the benefit of switching from a normal distributed variable to standard normally distributed variable ?

• Replies: 7
• Views: 7,463
01-20-2011, 04:56 AM
32. ### ANOVA sums of squares proof

How can I prove that a constant d can be added to each x_{ij} without affecting any of the ANOVA sums of squares? I know the computing forms of...

• Replies: 2
• Views: 7,462
02-05-2011, 04:22 PM
33. ### Approximate Average

Hi, I am very new to statistics, just started a couple of days ago and have a question: Why do we use approximate average in sample variance? Why...

• Replies: 5
• Views: 7,452
01-15-2011, 01:44 PM
34. ### Significance level question

A group of researchers fails to find a significant effect that they predicted. Assuming this effect exists, what should the researchers do in order...

• Replies: 6
• Views: 7,451
03-20-2011, 02:10 PM
35. ### RPD Acceptance

I am analyzing duplicate water quality sample data (2 samples collected in the same place at the same using the same procedures). I was told to use...

• Replies: 1
• Views: 7,448
10-02-2009, 10:58 AM
36. ### Computing Z-Scores #2

The following data represent the number of inches of rain in Chicago, Illinois, during the month of April for 20 randomly selected years. 2.47,...

• Replies: 2
• Views: 7,435
02-26-2006, 08:30 PM
37. ### Who can solve this AP Stats problem?

An agricultural field trial compares the yield of two varieties of tomato for commercial use. The researchers divide in half each of 10 small plots...

• Replies: 1
• Views: 7,432
01-15-2010, 01:19 PM
38. ### Excel 2007 t-test

I am trying to do a t-test for two samples. The question asks me compare the mean salary of sample1 and sample2. I know how to do a t-test in excel...

• Replies: 12
• Views: 7,425
10-14-2011, 09:27 PM
39. ### tests for continuous independent variable and categorical dependent variable

What tests could i use to determine the effect of continuous independent variable to categorical dependent variable? I am trying to detemine the...

• Replies: 0
• Views: 7,421
02-20-2009, 07:25 AM
40. ### Normal distribution, outliers, and the median

Hi: I have some data that should have an underlying normal distribution. However, there are some extreme outliers. To estimate the mean and...

• Replies: 5
• Views: 7,415
06-11-2010, 03:19 AM
41. ### When to use separate ANOVAs

Greetings, I've been struggling with trying to determine when to use several different ANOVAs or when to use one large ANOVA. Many of the projects...

• Replies: 7
• Views: 7,412
12-17-2008, 05:52 PM
42. ### test of normality on large sameples - also ks or shapiro-wilk?

if you have a large sample size...say 1000...do you still need to run and report tests of normality? I always thought you did but in my text book it...

• Replies: 4
• Views: 7,409
01-15-2011, 04:40 PM
43. ### How do I Analyze Likert Scale Data

My original goal: Prove that the JROTC program would still meet minimum enrollment requirements of 100 students if the program implemented a fitness...

• Replies: 1
• Views: 7,405
01-30-2011, 11:33 PM
44. ### I am not sure how Central Limit Theorem, and the t-distribution fit together.

Hello, By Central Limit Theorem CLT if the sample size is large enough, the distribution of the sample means is approximately normal. This result...

• Replies: 7
• Views: 7,403
BGM
03-14-2012, 12:36 PM
45. ### [SPSS] Mixed Models - How To?

Hi everybody, I've trying to understand how linear mixed models work within SPSS and how to set up my data to run through one. Ive read the...

• Replies: 3
• Views: 7,399
03-20-2012, 11:07 AM
46. ### Simple linear regression - Do I include the constant in the equation?

Hello, I am hoping someone can help me with a few regression questions. I am running a number of simple linear regressions....Do I want to (should...

• Replies: 4
• Views: 7,397
02-13-2006, 12:11 AM
47. ### Two-way repeated measures--post-hoc analysis?

Hello, I have run a repeated measures two-way ANOVA using SAS. The repeated measure is time and it shows that it is significant in an interaction...

• Replies: 4
• Views: 7,395
10-28-2011, 04:02 AM
48. ### t-score sample sizes

Hopefully someone can help me with this.... I am projecting forward two fish stock populations for a 10 year period with different levels of...

• Replies: 4
• Views: 7,394
07-06-2007, 12:00 PM
49. ### What is the unique advantage of Wald test and score test?

Since LRT is the most pwerful, why do we need the other two? :confused: Thanks.

• Replies: 3
• Views: 7,392
11-17-2010, 07:06 PM
50. ### Z-Score?

Hi, I'm having a problem figurung out what this question is asking: "Find the number Z such that the proportion of observations that are less...

• Replies: 2
• Views: 7,388
09-13-2006, 07:59 PM
51. ### Calculate Rho from Durbin-Watson Statistic

Have a test in an hour so probably wont be answered but on the practice test there is a question: "If the DUrbin-Watson statistic equals 1.6, then...

• Replies: 2
• Views: 7,381
12-04-2007, 12:47 PM
52. ### Consistent Estimators and Consistency in Mean Square

Hello, I have an estimator \hat\theta = f(X) and I know that f(X) has two possible values under this probability function: P(f(X) = \theta /...

• Replies: 26
• Views: 7,377
12-02-2011, 12:12 PM
53. ### How do I identify the test statistic?

Please help! I am stumped and I have no clue how to work this problem. Any help would be greatly appreciated! Thanks Listed below are ages of...

• Replies: 3
• Views: 7,370
07-29-2015, 01:56 PM
54. ### Nonparametric post hocs

Hi all, I am analyzing behavioral data from experiments I have conducted. I have used the Kruskal-Wallis nonparametric ANOVA to identify if...

• Replies: 2
• Views: 7,364
02-23-2006, 08:08 AM
55. ### Looking Up / Interpreting p Value for z values

Hi all, Another question. May be a silly question but my brain often gets tangled when going from book to application. After hours of...

• Replies: 7
• Views: 7,359
04-14-2009, 05:47 AM
56. ### find underlying distribution - how ?

hi all, a naive question, i have a dataset and i need to find out whihc one of the three (normal, poisson, log normal) generated it. i must use...

• Replies: 2
• Views: 7,358
03-21-2010, 02:27 PM
57. ### Central tendency and percentile

Can any of the following be true with a data set consisting of 1,000 values that are all different? If so, can you please explain why:eek: The...

• Replies: 8
• Views: 7,344
09-24-2010, 08:04 AM

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.