1. Announcement:
Dason ‎(Devorador de queso)
05-10-2017
Views:
1,775
+ Post New Thread

# 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: 196,542
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: 66,610
09-30-2005, 09:44 AM
1. ### Equations from properties of estimators

From my textbook, on the chapter on properties of estimator I get the following: E(1/n*∑Yi^2-2Yi*Y︠+Y︠^2)=E(1/n*(∑Yi^2-n*Y︠^2) I get instead...

• Replies: 1
• Views: 1,019
BGM
10-25-2012, 12:33 PM
2. ### Expectations Question ~ One within another, assigning grades question

I have a question regarding a practice problem I am trying to solve that I was wondering if someone was kind enough to help me gain insight in. ...

• Replies: 0
• Views: 1,790
10-25-2012, 06:56 AM
3. ### Statistics - Comparing Dose Response Curves

So I've got a stats question for anyone who can help; "You are testing the effects of a new drug that has been synthesized as an example of a...

• Replies: 4
• Views: 9,578
10-25-2012, 05:31 AM
4. ### Formula for Bonferroni vs Scheffe

Hello, :) Do you need different formulas for Bonferroni? Or can you still calculate: F = SScontrast/MSerror MSerror = SSerror/dferror ...

• Replies: 0
• Views: 2,516
10-24-2012, 11:49 PM
5. ### ANOVA or Kruskal Wallis

Dear Stats experts here... I have a question: I am counting cells in histology slides of certain timepoints after a treatment. day 0, day...

• Replies: 13
• Views: 4,335
10-24-2012, 11:09 PM
6. ### How to find Z-value given probability?? PLEASE HELP

Hi, I'm struggling on how to find the z value given the probability (working backwards using the table). Here's an example: The demand for a...

• Replies: 1
• Views: 2,880
10-24-2012, 08:48 PM
7. ### need to know number of product view to purchases I need to make a decision

On my golf equipment website, if on average 1% of product views lead to a purchase, how many views do I need on a new product to determine if it is a...

• Replies: 2
• Views: 2,037
10-24-2012, 07:30 PM
8. ### Testing for concordance

An interviewer administered questionairre was carried out amongst twenty participants from a population of around 50. The requests were sent to all...

• Replies: 0
• Views: 849
10-24-2012, 04:28 PM
9. ### Simple regression vs Multiple regression - how to answer this question

I am working on an assignment and stuck on whether I need to use a simple regression or a multiple regression. Any help would be appreciated. ...

• Replies: 1
• Views: 1,194
10-24-2012, 04:21 PM
10. ### Statistical Inference - Parameter Space

"Suppose that (x_1, ... ,x_n) is a sample from a Bernoulli(\theta) distribution with \theta an element of unknown. We take the parameter space to...

• Replies: 1
• Views: 1,588
10-24-2012, 08:05 AM
11. ### CDF questions.

hi, given the pdf and cdf of 2 functions ( X,Y) --> bivariate AND the CDF of function X and Y seperately, is it possible to find the mean and...

• Replies: 1
• Views: 1,361
10-24-2012, 07:53 AM
12. ### Scheirer-Ray-Hare test

Hi, can I use a Scheirer-Ray-Hare test on an analysis where one factor has 2 levels and the other one 11?? A more general question would be can I use...

• Replies: 0
• Views: 2,292
10-24-2012, 05:03 AM
13. ### Deriving Formula from Ordinal Regression Results to Classify New Cases?

What is the correct method for deriving a formula from the results of an Ordinal Regression, that can be used to predict the value of the dependent...

• Replies: 0
• Views: 986
10-24-2012, 12:47 AM
14. ### Exponential Distribution

Edit: Sorry, I realized after posting that my question didn't make sense as stated.

• Replies: 0
• Views: 1,191
10-23-2012, 11:00 PM
15. ### Corresponding Standard Deviation Question HELP

Stuck on this question from a practice test how do I go about solving this problem? A book collector has 12 copies of book A and 85 copies of book...

• Replies: 5
• Views: 5,779
10-23-2012, 10:05 PM
16. ### multivariate statistics help

i'm currently stuck on a past paper question, you may find this as difficult as i am, but if you don't then please explain how to approach this,...

• Replies: 0
• Views: 1,336
10-23-2012, 08:55 PM
17. ### Sports Stats Question

Hello Talk Stats, I am a new member from Australia and was hoping you might be able to help a sports fan with something I have been musing...

• Replies: 1
• Views: 2,078
10-23-2012, 05:49 PM
18. ### Meaning of bootstrapping residuals

What does it physically mean when I bootstrap residuals in a regression problem. Like when I bootstrap residuals and create synthetic data does it...

• Replies: 1
• Views: 1,165
10-23-2012, 02:13 PM
19. ### Upside down and backward "e"

What is the name of an upside down and backward "e"? Also, what does it stand for? I am looking over equations used in maximum likelihoods and keep...

• Replies: 6
• Views: 5,502
10-23-2012, 01:53 PM
20. ### Visualize and quantify factors that most contribute to customer decision

To the Direct Marketing department I have to to visualize and quantify the factors that most contribute to a customer’s decision to buy any group of...

• Replies: 8
• Views: 1,430
10-23-2012, 09:34 AM
21. ### Finding percentile

Hi everyone, a lot of questions asked on here was about finding a certain precintile, but my question asks to find the precintile. The only...

• Replies: 1
• Views: 1,307
10-22-2012, 07:40 PM
22. ### I don't get this question at all

So my teacher gave us practice questions for a test review and i dont understand these questions at ALL. Can someone please explain how to do...

• Replies: 1
• Views: 2,122
10-22-2012, 12:15 PM
23. ### How to compare more than 2 percentages

Hi, I want to compare percentage mortality of 4 groups of treatment of my specimens. Which test should i used? I know that i can use chi square...

• Replies: 0
• Views: 1,292
10-22-2012, 09:40 AM
24. ### Small population statistics - importance rankings

We are dealing with 20 responses - (population is 50 and was all targeted). We have some questions which required the participants to assign how...

• Replies: 0
• Views: 1,496
10-22-2012, 09:10 AM
25. ### Repeated measure ANOVA or mixed effects model?

Hi everyone, my goal is to understand whether a treatment modify the duration of the calls of a bird. I found not a similar situation in the...

• Replies: 3
• Views: 2,253
10-22-2012, 02:57 AM
26. ### Skewness and non-normally distributed data - Question.

Hello everyone, this is actually my first post as I have just discovered this amazing forum for talking about statistics. I've read through the...

• Replies: 9
• Views: 4,104
10-21-2012, 09:01 PM
27. ### Interpretation of low, negative, cubic clustering criterion values

Hello all, My question is how do you use the cubic clustering criterion to assist in selecting an appropriate number of clusters when the values...

• Replies: 0
• Views: 5,370
10-21-2012, 08:41 PM
28. ### Light bulbs problem

.....................................................................

• Replies: 0
• Views: 1,542
10-21-2012, 12:31 PM
29. ### Calculating Partial Eta Squared from Wilk's Lambda

Hello! I am doing homework for my multivariate stats class. Our teacher is asking us to calculate the partial eta squared using wilks lambda. The...

• Replies: 0
• Views: 5,168
10-20-2012, 09:12 PM
30. ### Hypothesis Testing - finding the power and beta!

A medicine dispensing machine is designed to discharge on average at least 8ml of medicine per dose with a standard deviation of 0.2ml. The amount of...

• Replies: 0
• Views: 1,599
10-20-2012, 08:00 PM
31. ### Odds Ratio vs Risk Ratio vs Relative Risk

I've conducted a risk factor analysis (for a type of injury) upon a prospective cohort. Part of this involved a chi-square analysis upon predictor...

• Replies: 0
• Views: 1,715
10-20-2012, 07:20 PM
32. ### Running a T-Test when you don't have mean/STDev

Hey guys, I'm currently enrolled in a statistics course right now that deals with Quality Improvement methods. The previous course acquainted us...

• Replies: 5
• Views: 1,722
10-19-2012, 12:04 PM
33. ### Normal Conditional Distribution

Anyone know answer to below. If two random variables X and Y are both marginally normal, and conditional distribution of Y given any value of X is...

• Replies: 4
• Views: 1,408
10-19-2012, 07:53 AM
34. ### Using Hypothesis test for decision making - find if sample represents the population

Hi All, I work with an NGO and we have a telemarketing department which purchases phone number databases for calling and marketing our cause. We...

• Replies: 7
• Views: 2,726
10-19-2012, 05:44 AM
35. ### How to workout the multiple comparison of means using common SED or SEM after ANOVA?

Hi, good day all. I have a problem here. I am doing an obesity research on 4 groups of mice. Each group contains 8 mice (n=8) I receive a...

• Replies: 0
• Views: 1,430
10-19-2012, 04:21 AM
36. ### Comparing this year's sales to last year's sales form a panel of pharmacies.

Hello I have sales of a product,by month, for February to August 2011 and the same period for 2012. The sales are from a panel of 500 pharmacies...

• Replies: 1
• Views: 1,572
10-19-2012, 03:07 AM
37. ### ROC curve help

Hi!, im new at spss, and dont know much about statistics in general... I have a group of ppl that answered the same questioner twice, but with a...

• Replies: 1
• Views: 971
10-18-2012, 10:08 PM
38. ### Survey Data analysis

Hi, I have a survey data that measures the conditions/noise levels and 3 other areas at the workplace(total of 5 areas).These are in turn used to...

• Replies: 0
• Views: 880
10-18-2012, 10:04 PM
39. ### Think my brain may explode!

Hi there, I have tried my best to answer this question myself, have read several text books and online support, and for some reason I am just not...

• Replies: 0
• Views: 1,395
10-18-2012, 05:11 PM
40. ### 76 percent per 1,000 women aged 15-19, U.S

Hello everyone, I am mathematically and statically challenged beyond belief. So, please riddle me this: If you look at the first paragraph of...

• Replies: 4
• Views: 1,598
10-18-2012, 03:12 PM
41. ### Who is more likely to win (mean score + standard deviation)

My teacher gave this as an example: "Scotland is going to play vs Tonga in rugby. Tonga has a mean score of 18 and a standard deviation of 13....

• Replies: 11
• Views: 2,710
10-18-2012, 02:09 PM
42. ### Distributions of random variables

I have been sweating over these problems for 4 hours - can someone please help? Let Z1,...,Zn be identically independently distributed ~N(0,1)...

• Replies: 9
• Views: 1,870
10-18-2012, 01:24 PM
43. ### Question

Student A scored a 90 on her Statistics test (M = 87, SD = 6). Student B scored a 90 on his composition test (M = 88, SD = 3). Which student did...

• Replies: 4
• Views: 1,621
10-18-2012, 10:09 AM
44. ### Conditional probability question ~ why is P(H) = P(HH)+P(HT)?

Hi, I am told that the probability of an unfair coin is the following: P(HH) = 4/9 P(HT) = 1/9 I need to find what the probability of...

• Replies: 2
• Views: 1,364
10-18-2012, 03:54 AM
45. ### experiment: estimating candies in a jar

this is an experiment project for my class. there is a big jar filled with 2 types of candies. we need to estimate 3 things: A. how many Type A...

• Replies: 0
• Views: 1,457
10-16-2012, 08:39 PM
46. ### Comparison of ordinal data - same subjects, same questions, 5 years later

Hi all, I'm looking for a good way to represent changes in ordinal-type data. I have 2 sets of data. In the first set, 50 companies (which...

• Replies: 0
• Views: 1,712
10-16-2012, 03:23 PM
47. ### Two-Way ANOVA question

Hey guys I'm new to this form. I've had trouble with stats over the past three years. I'm fourth year university and only need this one statistics...

• Replies: 0
• Views: 3,520
10-16-2012, 03:00 PM
48. ### Compare Treatment Effects of 2 Groups - Repeated Measures & Binary Outcome

Hi, I have two groups (1:non-comorbid group, 2:comorbid group), where patients in one group have a condition that patients in the other group do...

• Replies: 0
• Views: 2,720
10-16-2012, 01:50 PM
49. ### Using regressions in monte carlo simulations

Hey Guys, I'm building a valuation model with monte carlo and regression elements but could use a bit of help. The model breaks down the...

• Replies: 0
• Views: 1,242
10-16-2012, 09:39 AM
50. ### Simulation of unlikely events over random binary variables knowing their probability

Hi, I have n binary variables all having the same probability p of flipping. Probability is low, so I wouldn't want to go through generating a...

• Replies: 3
• Views: 2,171
BGM
10-16-2012, 03:27 AM
51. ### Please Help - How Do I Prove Hypothesis?

Hi, I am in 6th grade, trying to do an analysis of data for a science fair project. Sorry, but I am only at Algebra 1, I do not have any...

• Replies: 12
• Views: 3,040
10-15-2012, 06:50 PM
52. ### A bit confused on confidence intervals

Why does the t-value for the 98% confidence interval increase to 2.33 from 1.96? Basically what determines these values and what does it mean?

• Replies: 3
• Views: 1,752
10-15-2012, 03:19 PM
53. ### How can i determine which predicted value is more accurate?

Hey everyone, So i did a simple linear regression on the data below: Assigned questions: (c) Predict the heart disease mortality...

• Replies: 4
• Views: 2,726
10-15-2012, 02:33 AM
54. ### Quick Q

How would I calculate a sample mean if I'm given the standard deviation and sample size? The example in the book says "The volume of liquid in a...

• Replies: 1
• Views: 1,210
BGM
10-14-2012, 11:31 PM

+ Post New Thread

#### Thread Display Options

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.