When some of the patient-level data were released after an FOIA request and reanalysed, the claims made by the trial investigators were not substantiated.

I have made an FOIA request for patient-level data for six measures (questionnaires, scale scores, etc). I have asked simply for...

How much specific knowledge of a trial reqd to extract test results]]>

I am studying the relationship between burnout on GPA.

I wrote down my hypothesis as follows:

H1: Exhaustion will negatively affect GPA

H2: Distance will negatively affect GPA

H3: Competence will positively affect GPA

However, I have also two control variables and now I have conducted a Hierachical regression. However, I have the feeling I have to do 3 simple lineair regression, or is it no problem that I have conducted a multiple regrssion? , my supervisor wanted that...

Difference in hypothesis testing simple lineair regression or hierachical lineair regression]]>

I’m sitting a stats exam next month. A past paper question showed a forest plot and asked what type of study it had come from. The options included meta-analysis and systematic review. Systematic review was the answer. My question is, how can you tell the difference between a forest plot from a systematic review vs a forest plot from a meta-analysis?

Thanks in advance for your help.

Daisy]]>

But, when looking a time series, I was a bit confused:

Time series Residual]]>

I understood that I should not expect my residuals to be autocorrelated.

But what about the time series data itself, should I expect to find autocorrelation in them?

Tank you in advance.]]>

I have been working on this and from the book i am reading the answer is right, but it just does not feel right to me for some reason.

So the problem I am solving for is.

IF there are 6 cars that are made and 3 of them are junkers.

There are 2 dealers that receive 3 cars each (A and B).

What is the probability of this event occurring if, in fact, the three cars shipped to Dealer A were selected at random from the six produced?

So I came up with this.

The probability of A...

Calculation of the probability of multiple random events]]>

By rolling 5 times a dice I have the chance to get 3 twice first, then two different numbers and finally the number ''3''?

He uses a Bernoulli distribution to calculate the composite probability. let's suppose for a moment that the random variable is not a dice (containing a finite number of faces and numbers) but is an indeterminable event on which we can only make hypotheses. The Bernoulli...

Bernoulli distribution]]>

I have submitted an R package to CRAN; the package is quite small, as it features just one function and three toy datasets.

Before submitting to CRAN for evaluation, I have run a check within RStudio (hitting the 'check' button), and fortunately I got no error nor warnings nor notes.

I have just received an email from the CRAN guys, who informs me that the package "does not pass the incoming checks automatically"; the problem is with the Windows and Debian checks.

I am at loss of...

Submission of package to CRAN: problem grasping an Error]]>

I am currently into my postgraduate degree in Applied Biostatistics and I am trying to figure out an answer to the following issue:

I have been given the below dataset:

0 ------------ 5%

10 ------------ 8%

20 ------------ 9%

30 ------------ 7%

40 ------------ 11%

50 ----------- 14%

60 ----------- 22%

70 ----------- 28%

I have been asked to...

Interpolated Rates vs Initial Rates]]>

the way I explain p value: probability of observing effect when, in reality, there is no effect. This translates to probability of data given the null (null=there is no effect!). I was thinking that this is the same as saying "the probability of a false positive". But then I was told that it's wrong, because p value is NOT probability of an error. This is where I am...

p values, alpha, and errors]]>

1.1 Which one of the following might be one of the consequences of global warming?

a. Drought

b. Skin cancer

c. Acid rain

1.2 Which one of the following is the reason for your answer to the previous question?

a. Acid rain becomes more frequent as a result of global warming.

b. Global warming leads to an increase in solar radiation, which can...

How to do data entry & analysis of three-tier test?]]>

I've got a zero inflated, negative binomial GLM that I'm using and am curious what the best way to visually represent my results in figures would be. My model doesn't have a ton of factors; I'm looking at a blocking factor, a continuous predictor, the interaction between the two and two additional covariates.

Thoughts? Suggestions?]]>

I've built a model for total sales forecasting based on cumulative sales and using least squares regression gradient [y-intercept set to zero i.e. f(0)=0] to get the monthly 'run rate'. This works well for large, mostly consistent numbers (~300 per month).

e.g.

Code:

```
Month Sales Cml Sales
1 300 300
2 250 550
3 325 875
4 375 1250
```

Sales Forecast - Least Squares Regression or Arithmetic Mean?]]>

Mr. Rossi waits for a phone call from Mr. Bianchi who has announced that he will call, in an unspecified instant, between 4:00 pm and 6:00 pm. Mr. Rossi must however be away from 4.45 pm to 5.00 pm. What is the probability that the call arrives while Mr. Rossi is absent?

The instant of the call is a random variable X. As far as Mr. Rossi knows, every moment from 16:00 to 18:00 is possible, while outside this...

Density probability function considering a subinterval which have different probabilities]]>

I have been stuck on the following past paper question for the past week and still have not been able to find an answer. It is broken down into part A, B and C. If anyone is able to answer this question with explanation I will be eternally grateful.

Q:

Let X and Y be discrete random variables whose possible values are X=0 and 10, and Y= -20 and 10. The joint distribution of (Y,X) depends on the unknown parameter c. The probabilities of the possible values are given in the cells of the...

Need help, Expections and Joint Dist. Question]]>

I'm in need of help. I encountered an issue regarding my statistics.

Here some background about my research:

- I have 36 participants assigned in 4 Groups (independent variable, IV) based on differnt combinations of flexibilty.

- Number of participant per Group. Group1=7 ; Group2=9 ; Group3=11 ; Group4=9

- I have 25 dependent variables (DV) splitted in kinematic- (8DV) and kinetic (17) variables

- The research question is, how do flexibilties alter differnt kinematic / kinetic...

Help! Performance of multiple seperate MANOVA's]]>

The Chances of different event occurring in the game are:

Event A - 5%

Event B - 12%

Event C - 12%

Event D - 25%

Event E - 46%

Total = 100%

I am trying to make statistic that shows how many times will i have to play the game for Event A to occur atleast once with a 99% certainty.

So something like a confidence interval.

Thank you.]]>

I'd like to perform an ANOVA or similar with data whose residuals are nonnormal. My dependent variable is 1-7, but about 30% of my respondents provided 1's and the plurality of the rest provided 2's. I've tried log and square root transformations with no luck. Any advice on how to proceed?

Basically, the distribution looks like this (with each 1 representing an interval of 10 cases):

1

1

1

1

1

1

11

11

11

11 1

11111

1111111

1111111

Gratefully,

Psychmajor]]>

I have searched long and hard for anything remotely useful when it comes to predicting sales of new products that cannibalizes existing product portfolio. Now that I have found this oasis of clever minds, I hope someone with experience can educate me in this matter. Would be extremely grateful.

Goal: create model that accurately predicts future sales of existing products and newly launched products. With a possibility to change prices to see how such adjustments would...

Forecasting sales of new products with cannibalization effects]]>

I have data on 400 school students. For each students I have three dependent variables, all continuous.

In addition, I got several independent variables, such as the student age, gender, etc,...

Some students come from the same class. In the file I have data on the teacher: Age, gender, etc,...

I need to find which independent variables relate to the dependent ones.

I naturally thought of a mixed model, with the class being the random effect.

What I am not sure about, is how...

Setting up a mixed model]]>

I was asked the other day if I could determine whether two mean scores from a survey were statistically significantly...

Survey Statistics]]>

- We estimate a simple linear regression model y = b0 + b1*x + error The input data in our model estimation shall be:
- y = 1 month stock returns (cross sectional) for month n
- x = market cap for each stock (cross sectional) for month n

- We test if our coefficient b1 is statistically significant. And record the result for month n. We also record the R squared.
- We do step 1. & 2. for a total of N month.
- Finally we...

Is it permissible to aggregate results from multiple cross sectional regressions?]]>

I want to spot if there is a correlation between the number of Aces made by a tennis player during the matches and the number of matches won

I have two variable: the Aces and the matches won

The I have the months: Genuary , february, April

How do I need to categorize these (the months)? as variables? As factors? Sorry I am new

I would like a simple example to help me because the GUI is not working good, I have to use the terminal...

correlations]]>

Menu-driven X-12-ARIMA seasonal adjustment in Stata

And i also installed the x12a64 package on my PC.

Its location is under "C:\Program Files (x86)"

But when i try to run it, it shows me this

The package's adopath file is sadopath.so and looks like

Code:

```
*! version 2011-Nov-23
* sapath "d:\seasonal adjustment/y1.out" "e:/pbc tj/y2.udg"
program sapath, rclass
version 11.0
syntax...
```

we have to groups of subjects, A and B, and N measures.

If we test all N measures for differences between A and B we obtain N p values (let's call this set P0).

The, we propose a way to extract subgroups from one of the two groups say A1, A2 (whose intersection is null and whose union is A).

Now, we have N p values for the test A1 vs B, and N p values for the test A2 vs B (let's call these sets P1 and P2 respectively).

What is the correct way to compare P0, P1, and P2?

thanks]]>

I'm currently doing a research that requires me to use annual precipitations by country and year (panel data).

I wasn't able to find this information online (if anyone has any idea where I can get such information, I would be forever in your debt).

I was able however to find monthly average precipitations. Do you guys know how I can get the annual mean or variance from the monthly means?

Thank you for your help, I really appreciate it.]]>

In a Chi Square goodness of fit test, and also in a Chi Square test of independence, what are the criteria for when direction can/must be stated in the conclusion?

For example, "A boy is interested in whether cricket captains call heads and tails equally at the pre-game toss. A survey of 100 matches shows that heads was called 62 times and tails 38 times. What would you conclude of the captains' calling habits?"

Running a chi square goodness of fit test I have Chi-square(1, n=100)...

When is direction implied for a Chi Square test?]]>

Accuracy of Regression Results?]]>

Here's my situation. I need to determine if the incidence of a categorical phenomenon that I have observed in a sample is significantly different from an accepted incidence of the phenomenon published in the literature. I would generally use a Chi square test in this situation but my reference incidence is reported as only a percentage...

Statistical significance of observed incidence]]>

I have sets of data I want to analyze but I'm not sure how I go about it. I am looking at sprinting training/competition data and I am looking to do some sort of regression in order to get a basic predictor model for future races. Unfortunately, it's not as easy as doing a linear regression since the outcomes are not continuous but discrete (1st place, 2nd place, 3rd place...

Analyzing data with continuous variables + discrete outcomes]]>

As a requirement for express entry I need to show the average balance of my bank account for the last six-month, problem is that I don’t know the formula, could you please help.

Thanks ]]>

Perhaps unwisely as a newcomer to stats, I have taken on a scale validation project. I’ve searched the literature and can’t find anything so this is the issue:

I’m developing a scale that (hypothetically) will identify, differentiate and measure two different constructs occurring in parental/child relationships.

I’m allowing my participants to redo the scale questions for each child that they have (using Qualtrics), so each parent may complete it once or twice or nine times depending...

Factor Analysis newbie seeks your help]]>

We tried comparing the 2 data sets...

Assessing how good a model is]]>

[video]https://www.youtube.com/watch?v=bEwqFe_eiKI[/video]]]>

I am unsure with an interpretation of the results ofmy fixed-effects model.

I conduct a fixed effects analysis, similar to this one:

xtreg number_of_cigarettes = constant + beta0*year + beta1*treatment + X, fe

Now, the number of cigarettes is only stated for individuals who previously answered to smoke.

My beta1 gives me a negative coefficient of let's say -2.

Is it correct for me to say that the effect can be driven by two factors:

1. individuals smoke less (that one is...

Fixed effects interpretation - dropouts]]>

I was thinking to use Google Cloude machine learning / deep learning to forecast the odds of an event. I would be thankful if you suggested to me a software for predicting models which it would be simple to use for someone who is not pratic on statistic and coding. I would be able to set my own PERSONAL variables give them a value and play around with these variables, without needing to code

Any suggest for a...

Best machine learning algo to have odds on a match?]]>

This is the grahic:

]]>

Given these numbers:

2, 3, 4, 8, 10, 15, 22

and here the number of days (each number for the correspective day, so 2 *1day, 3*2day, 8* 4):

1 2 3 4 5 6 7

Calculate the Weighted mobile average and the Esponential moving average

I know the formula for calculating the Weighted mobile average, but I can't understand the formula for Esponential moving average:

EMA...

EMA and WMA computation]]>

I have a problem related to statistics, and I hope that you can help me out. First, an attempt at a short version of my problem:

I have 2 data sets that consist of 3 sub-sets each that I want to compare with a methodology that takes the order of the data points into account.

Now, for the actual details.

I have multiple data sets of 3 sub data sets each, the latter of which sort of belong together. For any given set, data point 1 of sub data sets 1, 2, and 3 are based on the...

Comparing groups of data sets with the order of data points being taken into account]]>

Now, we aim to do a couple of tests to check the quality of the survey, like:

- Basic validity of questions

- Ceiling effects

- Inter-rater reliability

- Do the items load properly, and are the 4-item scales reliable?

However, we keep running into the problem that people only...

Performance review]]>

I have approximately 800 items, that were

independently

assigned into 3 categories (Buy, maybe, Don´t Buy), by

two reviewers.It looks like:

Item 1; Buy; Buy;

Item 2; Don´t Buy; Buy;

Item 3; maybe...

Assess Reviewer Performance]]>

To assess the impact of the environmental gradients on samples or taxa, they should be projected orthogonally on the...

Canonical Correspondence Analysis: how to interpret results]]>

I don't know many terms, and what it's super-difficult is also to learn R language and tools in R, how do they work.

I am mining data on tennis. I have a lot of data about a tennis player.

I want to find some correlations.

I target tennis players. I want to know if there is a correlation between a tennis player's...

Prediction models and correlation in R]]>

I'm a psychology masters student in the UK. I failed GCSE maths and have dyscalculia, so stats is challenging for me, though weirdly enjoyable....]]>