What is the proper way to compile the data into an overall ranking, and what is the proper way to report this on...

Ranking question]]>

I suspect that this means that multilevel models are more tolerant to differences in sample sizes than, say, ANOVAs. However, does any know _how_ tolerant they are? I've looked around, but can't find...

Guidelines on Unequal Sample Sizes in Multilevel Models]]>

I have a dataset that has geographic data (county-level data of cancer incidence) which has a large variance. For each county, I have a list of county-level characteristics (socioeconomics, environmental, etc - e.g. obesity).

I want to understand the contribution of the county characteristics to the geographic variation in cancer incidence. What test should I use?

I was thinking of using linear regression, but many of these county-level characteristics are colinear (e.g...

Variance contribution testing]]>

I am pretty new around, and my statistical studies were taken more than 20 years ago, so my skills in the area are totally rusty.

Still, I recently I bumped into an interesting case which made me wonder if I can still revive something of the old glory.

Let's say we have an INITIAL value, to which 6 features (Feat1, Feat2, ....., Feat6) can sum up, giving a FINAL value.

These features have some other maximum 6 mini-features at their turn, (for ex Feat1 has 5: a1, a2, a3, a4 and a5)...

Multiple regression case?]]>

I am new to this forum and I wish someone can help me here. Would someone help me to identify the name of formula used below? Thanks!

Every quarter, we receive projection from other department and their projection are in quarterly basis, I have to convert the quarterly data into monthly data, and we use the formula below for conversion.

For example, if we want to get April 2018 (First month result), May 2018 (Second month result) and June 2018 (Third month result)monthly data...

What is this formula? Used to convert quarterly basis data to monthly basis]]>

or look at the variance and only consider correlations greater than, say, 0.5

or use both: a p value of less than 5% and a correlation greater than 0.5?

p.s. I thought I'd posted this yesterday, but cannot see it.]]>

Still, I would like to try to refresh a bit my knowledge and, especially when I bump in some minor problems I can meet in real life, maybe even try to solve it with a bit of help. Hope you'll not be too tough with an old rookie! ]]>

As an example, here is some made up data:

Code:

```
data DID;
input ID time group value;
cards;
1 1 1 1
2 1 1 2
3 1 1 1
4 1 1 3
5 1 1 2
6 1 2 5
7 1 2 4
8 1 2 6
9 1 2 4
10 1 2 6
1 2 1 5
2 2 1 4
3 2 1 5
4 2 1 6
5 2 1 5
6 2 2 6
7 2 2 6
8 2 2 7
9 2 2 5
10 2 2 6
;
run;
proc means data=DID mean;
class time group;
var value...
```

So for my honours research project, I decided to answer the question of whether it is a good idea to invest in the tourism industry in south africa or not. I attached the excel file (which i had to convert to pdf so that it would upload, so if you could just covert it back to excel file once you download it).

So from this file i will be using all variables at actual figures and current prices, but i will only be considering the data for January of each year (2007-2017).

Please can i...

Which statistical test to use]]>

I have an age & sex matched-group of patients.

Control group and study group both had the same operations. Control group had no intraoperative fracture complication. Study group had intra-operative fracture complication. Study group also has two subgroups (two different surgical approaches).

All patients had preoperative and postoperative outcome measurement (out of 100 points).

Should i use Mc Nemar's for control - study group, and also subgroup comparison for clinical outcome...

Should i use McNemar's for a matched-pair study?]]>

A stock is selling at $50 now. Based on a 90-day linear regression (i.e., 90 historical periods), 80 days from today, the stock will be selling at $56. The standard error is 4. What is the 95% probability that the stock will be selling at least at $59? Using Excel, how is the 95% probability calculated?

Thank you!

Tony]]>

I am measuring the % population of dead cells on a time course (96 hours) post drug treatment (hour 0).

I measure the dead cell population every 24 hours giving me 5 data points.

I also measure the glucose concentration (starts at 12mM) at each time point.

If that is not enough data I also have the same experiment done again but starting at 50% glucose (starts at 6mM) and I have completed all the above on 6...

Dont know which statistical test I should use?]]>

Mixed Modeling for Longitudinal Data]]>

Anybody have a common experience?]]>

I would like to know what would be the best method to measure the relationship between variables like life expectancy and income over time (years)? In my case I have a time series with around 30 years. I would like to examine if there is a dependence between variables like life expectancy and income over time.

Thank you in advance and greetings from Germany!]]>

time series analysis]]>

I am trying to put togheter an R function to test if points in a given area tend to occur closer to any point belonging to another set of point, or if they are distributed irrepsective of the distance from the latter.

I would like to have some feedback on the method I applied, especially on the use of the binomial distribution.

With reference to the attached image, let's imagine we have some locations (crosses) and some other locations (red dots). For the sake of argument, let's...

testing the association between points and any of the points belonging to another set of point: am I approaching it correctly?]]>

I hope you can help me with the following question.

I measured the power input and output of a storage and retrieval vehicle with 1,000 single measuring points. I repeated the measurement five times with the same measure method and same time steps. The result is five measurement series with 1,000 measuring points. Now I calculated the standard deviation of the five values of every single measurement point. Is it now on statistical/mathematical aspects permitted to calculate the...

Average of standard deviation as repeat accuracy for five measurement series]]>

Is it correct to enter the total costs as the dependent variable (for all records in the database, independent of cohort assignment) and enter all independent variables (age, gender, premedication…) into the...

Generalized linear model for cost data in spss]]>

I coach a hockey team and we collect a lot of data on our performance. While I'm reasonably numerate, my statistics skills are limited to pretty basic things. So here's my problem.

We collect data each game which feeds into a process measure that provides insight into how our team played in a game (independent of the outcome of that game). I'd like to be able to look at that measure over time (i.e., as the season progresses), but looking at the raw measure would be useless...

Standardizing Performance (sports-related)]]>

The official manual for use states to convert raw scores into t-scores and then to use cut-off scores to see if participants are at high, normal, or low risk for three variables in measuring compassion fatigue. However, the manual also has cut-off scores for raw scores alone.

When analyzing the data, the levels of compassion fatigue for the raw data...

Using ProQOL Questionnaire for Project]]>

ARIMA]]>

(sorry, I know it is a simple question, but I have depleted my resources...!)]]>

In how many ways can 3 balls be drawn from a bag of 12 balls for 4 consecutive times without replacement?

My solution was 12C3+9C3+6C3+3C3, but his solution was 12!/(3!*3!*3!*3!). He didn't explain why my solution was wrong though. But I really feel that I'm correct on this one]]>

`library(GmAMisc)`

) and run a function, an error is returned:If I visualize the code, copy and paste it in the R console, and re-run the function, it runs as expected and no error is returned.

I am wondering what is...

function trows an error at first, but runs smoothly after being copy/pasted]]>

Participants will view sixteen everyday scenes. Each scene represents an experimental trial. In each trial, two almost identical images appear one after the other, with an intervening blank screen. The images and the blank screen appear for 0.25 seconds each, providing the experience of the screen.

Participants must view the images presented and try to detect whether any change has occurred...

Which test to use?]]>

Schools are divided equally into intervention and control group. We might expect...

Anonymous data within schools - how not to just use group mean over time - looking for references]]>

I have a dataset with 5 observations (5 years) nested within each case. I am not sure if a multilevel logistic regression can be ran using spss or mplus, and the syntax for running it if so.

Any advice on this will be appreciated.]]>

C-like:

`p.x <- round((factorial(n.of.points)/(factorial(x)*factorial(n.of.points-x)))*(p^x)*(q^(n.of.points-x)),5)`

making R computing large factorials]]>

Logit Model_Predictive Regression]]>

Happy New Year. Wish you a very successful year!

I am creating PCA plots in R in an automated way and need a script to define whether the sample (red dot on the figure) is outside/within the circle. Does anyone have a good solution for it?

So far I've been using mahalanobis distance and then seeing whether the distance for the sample is within 80th percentile or not. The problem is that mahalanobis distance is in the multidimensional space, while pca plot is shown in 2D. So...

how to determine whether the point is outside/within the ellipse in PCA]]>

We are undergoing a dissertation about the measurement/level of preparedness of banks when it comes to the uprising risks of potential lapse on their system, we've incorporated the concept to "contingency planning" , we have a set of questionnaires for them to answer on how they are prepared on the impact of a system lapse. The question were answerable by YES, MAYBE and NO. We ONLY PICKED 3 banks as our respondents. What statistical tool should I use in interpreting the data...

No idea what statistical tool to be used. Need help]]>

I'm battling to do bias correction for my data, could you suggest simple methods for it please.]]>

I have tested 7 similar sound devices.

For each device I asked to evaluate its sound characteristics, using dichotomies, e.g. “cold” “warm”. This evaluation is done with a scale, see below (they had to tick the appropriate vertical line)

cold warm

∣ —— ∣ —— ∣ —— ∣ —— ∣ —— ∣ —— ∣ —— ∣

I had 11 dichotomies.

37 people completed the questionnaire.

My question regards reliability:

When I do a cronbach’s alpha for the...

reliability]]>

I need your help in calculating growth rate/trend

I do not want to use the existing definition of growth rate.

An example is below of a customer spending details per week

1 10

2 20

3 45

4 55

6 20

7 0

8 0

9 5

I need to know whether the customer in increasing his spend or not and by how much is average week on week growth rate.

I need to do this for a list of customers.

Regards,

Ashwin]]>

Linear Probability Model]]>

....]]>

Okay so I've managed to sort out most of my exploratory stats but what's bugging us now is over-representation. For e.g. my dependent variable is categorical: Introduced, Naturalised, Invasive.

Species per status sits at:

Introduced: 20 species absolute count = 15.5 preportion

Naturalised: 80 species absolute count = 50 preportion

Invasive: 60 species absolute count = 37.5 preportion

Now when you run tests the programs automatically use the absolute count to spit out numbers and...

Proportionate vs absolute count for analysis]]>

quantile regression with a bounded dependent variable]]>

1). Some papers I look at report a weighted kappa statistic, while others do not (even though some outcomes have 3 categories of mild, moderate and severe). The weighted kappas will give...

Meta-analysis of kappa statistics]]>

Im currently doing my MSc in Nature Conservation but I've always struggled with stats.

At the moment my data set holds categorical data (which

I just want to run basic tests to understand my data but cannot get beyond pivot tables. From what I've googled I wont be able to run an Anova because my data is wrong for it, a Chi Squared wont work because my categories are not numerical. T-test wont...

Small question, big help - Stats]]>

In Life

Some mock me for doing statistics

Some loathe me and statistics

Some don’t understand what statistics are

Why is it that statistics

Put a calm smile on my face?

Because of statistics I can solve the deepest mysteries

Because of statistics I will not be lonely again, playing in the data

Because of statistics I can rearrange the stars in the skies above

(by Chinese statistician Wang Jiaowei [translated],

The...

Statistics Poetry]]>

(a) Why is testing for a normal distribution important?

(b) Why is testing for skew and kurtosis important?

(c) What role does hypothesis testing play?

(d) What distribution is used for constructing confidence intervals?

(e) Why decompose (STL) a time series?

(f) When do we use EDA?]]>

We are performing a follow-up study of a medical test, investigating if it's useful for predicting mortality. I've spent quite a few hours trying to estimate the sample size needed to perform a valid study but I'm still very unsure how to go about this, and I believe I'm at the top of confusion right now... I therefore seek your help!

Estimate sample size needed for valid study of medical test]]>

I can do a regular linear regression like

Below is how he do it:

1. He first consider that spread ~ (

Step by step regression]]>