Hypothesis testing assesses whether data support a given hypothesis rather than being an effect of random fluctuations or some other process described by an alternative hypothesis.

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22 views

Paired difference t-test vs independent two sample t-test to assess means difference

If I want to compare two sets of measurements, i.e., how much their means differ or how much the sets differ, I would say I have two options: Paired difference t-test: Calculate the differences to ...
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0answers
8 views

hypothesis Test on Sal [duplicate]

I was going thru Sal Khan's video on Chi Square https://www.youtube.com/watch?v=2QeDRsxSF9M and was wondering Why can't this hypothesis be used: "H0: Distribution not correct and H1: Distribution is ...
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0answers
9 views

Fisher test interpretation for left or right sided p-values

Let say I have a frequency table of two variables $x$ and $y$ having or not having some property. $$ \begin{array}{lcr} \mbox{} & x & y \\ \mbox{has property} & 20 & 2 \\ \mbox{does ...
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0answers
19 views

Derivations of Statistical Tests [on hold]

I am familiar with Z-tests, T-tests, F-tests, chi-squared tests and a few others. I know how and when to use these tests, how to find p-values and how to derive confidence intervals from the tests ...
0
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1answer
29 views

Does a lower t-stat suggest better evidence for rejection? [duplicate]

Say I have these two models: $y = \beta_0 +\beta_1x_1 + u$ $y = \beta_0 +\beta_1x_1 +\beta_2x_2 + u$ and the $p$ value for $H_0:\beta_1 = 0 $ with $\alpha = 10\%$ for both is less than 0.001, but ...
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0answers
17 views

Clustering MVT response data by audience

We are doing multivariate testing 4 possible values for each of 3 variables on a landing page: (a) offer presented, (b) product claim message displayed and (c) image used. So, 12 dummy variables, 64 ...
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0answers
11 views

Hypothesis Test: Difference in Rates with Null Values

I am trying to test whether a difference in rates is significant, where either the numerator and the denominator can be 0. What is the most appropriate test to use? For a specific (imaginary) ...
4
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2answers
56 views

Can I use likelihood-ratio test to compare two samples drawn from power-law distributions?

I have to compare two large samples ($N = 10^{6}$) of discrete data drawn from power-law distributions to assess whether they are significantly different. I can't do that by means of a two-sample ...
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0answers
12 views

When can one use Hochberg's or Hommel's method for adjusting P values?

The p.adjust function in R can produce P value adjustments based on methods from Hochberg and Hommel, which are both more powerful than methods from Bonferroni and ...
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0answers
16 views

Estimating the false discovery rate under the F-test statistics

We have food as a factor that can take in 3 values and 2 test scores as dependent variables. Basically, there are $k$ students who consume one of these food types before taking both tests. We want to ...
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0answers
19 views

One-way ANOVA: Concluding one true differences without any post-hoc tests?

Let's say that I run a one-way ANOVA with 3+ levels and that it comes out significant. Can I then, from this result alone, conclude that at least the two sample means that differs the most in my data ...
2
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1answer
19 views

Interpreting results of prop.test()

Suppose that I have two approaches to a particular problem. Approach A is observed to succeed 685 times out of 1347 attempts. Approach B is observed to succeed 2100 times out of 3748 attempts. I ...
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0answers
8 views

How to apply AIC to a situation where the mean of a multivariate normal is a 0-1 d-dimensional vector with exactly k 1's

I am trying to apply AIC to estimate mean in the following case: Let us consider that I have $n$ random variables $X_1, \ldots, X_n$, drawn i.i.d. from a normal distribution of mean $\mu\in\{0,1\}^d$ ...
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0answers
12 views

Slope versus Slope Change [on hold]

Is there a difference in the definition of Slope versus Slope Change? I am doing slope and level change calculations for my dissertation. I can't seem to find the answer if there is a difference.
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0answers
10 views

Best test for a ordinal and a continuous variable? [on hold]

My outcome variable is pain in a 10-pain scale and my independent variable is time (continuous). What is the best test to get a correlation? Thanks!
1
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2answers
84 views
+100

Inverted nonparametric rank test

I have two related samples, for which I want to prove they are not significantly different (normally you would test for the opposite, i.e. samples are significantly different). If I use Wilcoxon ...
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1answer
39 views

what should be the null hypothesis?

conduct a test hypothesis to show that it takes longer for people with average fitness to successfully complete physical therapy as compared to those with above average physical fitness. Test at ...
2
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1answer
43 views

One sample test of uniformity in R

I have a dataset of two columns: one with IDs and one with a column of single digits (0-9) (see below). I would like a statistical significance test for whether the data is uniform. Ideally, I would ...
1
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1answer
20 views

Critical value for Wilcoxon one-sample signed-rank test in R

I am trying to find the critical value for the Wilcoxon one-sample signed-rank test. Currently, I can find the value using tables. I looked at qwilcox() in R, but ...
4
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2answers
72 views

Using multiple comparisons corrections in Fisher p-value framework

I am wary of stepping into the civil war between Fisher vs Neyman-Pearson interpretations of $p$-value (which has been well elucidated here and here), but I've been pondering a question that I keep ...
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0answers
11 views

Is this R code of Rao score test for the Bernoulli data model correct? [migrated]

I am a complete statistical noob and new to R, hence the question. I've tried to find an implementation of the Rao score for the particular case when one's data is ...
48
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3answers
2k views

A psychology journal banned p-values and confidence intervals; is it indeed wise to stop using them?

On 25 February 2015, the journal Basic and Applied Social Psychology issued an editorial banning $p$-values and confidence intervals from all future papers. Specifically, they say (formatting and ...
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0answers
20 views

which method should i use for determining sample size?

what is the difference between the sample size determination method of using the critical values of the normal distribution with that of using the t-distribution? as an example if replication level ...
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0answers
8 views

Convert data to TS variable in AR [closed]

How can I convert my data to time series data in R? Firstly cpi <- read.table("y.txt", skip = 1, col.names = c("Time", "CPI")) Thanks
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0answers
18 views

Deriving the power formula of the one-sample proportion test

I have to derive the power of the z-test in testing $$ H_0: \pi=\pi_0 \text{ versus } H_1: \pi>\pi_0 $$ Denoting by $p$ the sample proportion, the power equals $$ ...
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0answers
11 views

Proportion and hypothesis [closed]

Manuscripts of a certain biblical text were produced in two forms, type A and type B. I a specific site, 10 copies of this text have been found, 2 of which are of type A and 8 are of type B. Assuming ...
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0answers
41 views

Bayes Test and decision regions

I'm given the following hypotheses: $$f(x|H_0) = e^{-x}u(x)$$ $$f(x|H_1) = 0.5\{u(x)-u(x-2)\}$$ and asked set up a Bayes Test for equally likely hypotheses and determine the decision regions. My ...
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3answers
106 views

How to find out if two sets of data are equal at 95% Confidence Level in R

I am interested to find a way to identify if two sets of data can be considered statistically different at 95% Confidence level (or any other). To be more specific, my data sets are composed of 5 ...
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2answers
25 views

White Test , testing for heteroscedasticity

i used a White Test for testing the homoscedasticity assumption of my linear regression I am working on. I have a problem whit the interpretation as I have a result from the test in which the p-value ...
2
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2answers
68 views
+50

Comparison of frequency rates

Patients with chronic schizophrenia will take some antipsychotic drug during some period of time. The frequency of schizophrenia for each patient will be recorded before and after that period. I ...
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2answers
82 views

Statistical test for difference in mean of means non-normally distributed, different number of cases

I have this data generated from simulations. For each "prob" I observe the mean value of cases with "rule" = 1,2,3 or 4. So in the example below, for "prob=.05" all cases with "rule=2" have a mean ...
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27 views

Testing hypothesis when each data instance is a vector

The experiment involved studying population body velocity changes during a marathon . Velocity of each person in control group and experiment group were measured at multiple instances during marathon. ...
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0answers
22 views

Strict exogeneity test in Stata [closed]

is there a strict exogeneity test I can apply in STATA? I'm trying to specify a Panel data model, and I would like to run a strict exogeneity test ( check that ui and Xi are uncorrelated), but can't ...
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0answers
20 views

Metaphors for understanding t-test? [closed]

Does anyone know of any metaphors or analogies that make understanding the t-test easier?
1
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1answer
29 views

Comparing Proportion of Positive Tests

A condition or disease (D) is measured using two different methods (A and B) in a sample of 1,000 individuals from a population. Using method A, the percentage of positive cases is 25%, whereas method ...
3
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2answers
101 views

What does an error in ANOVA indicate?

When I came across ANOVA, the instructor talked about df(Error), ss(Error), etc. What do these error terms indicate? Do error terms differ for two-way ANOVA with dependent and independent variables? ...
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0answers
18 views

Can one manipulate data to demonstrate the power of the analysis?

I was asked this question about the demonstration of power. There are two groups of data, say control and treatment. If conducting a test( say a linear regression including other factors, but the ...
3
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1answer
127 views

Significant t-test results accurate or random?

I've performed a bunch of independent t-tests looking for a relationship between 10 different variables in group A and 10 different variables in group B. There seems to be very few significant ...
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0answers
15 views

On a variable addition test

I'm having some difficulties in understanding the Variable addition test as is described in the pictures below. My small doubt is how can we have the same error term in equation (3.7.4) and (3.7.5)? ...
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0answers
10 views

Comparing proportion of categories in samples of different sizes

Maybe this is a very simple procedure, but I have been trying to find the appropriate method and I am getting confused. I have data from two different surveys. In the first survey (s1) there were ...
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0answers
10 views

difference between result and measurement

What is the difference between False Positive Result and False Positive Measurement there?
2
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5answers
322 views

What are the appropriate Statistical tests when dealing with two or more categorical outcome variables in a model

I'm familiar with GLM techniques when dealing with continuous outcomes and categorical or continuous predictors. I've used Logistic regression with a single dichotomous categorical outcome variable ...
1
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0answers
36 views

How to use difference in mean team weight to predict winner of college football game

I think I need a new statistic. I am trying to make the case that the average weight difference between college football teams is related to won-loss record. I am studying the Big 10 and Big 12 ...
1
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0answers
18 views

Independent t test significant but post-hoc planned analysis not

I was analysing two sets of data. In most cases for the study post hoc planned comparisons identified significance (<0.05), however for one sample, this was not achieved. However an independent t ...
3
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3answers
131 views

How to test if my distribution is multimodal?

When I plot a histogram of my data, it has two peaks: Does that mean a potential multi-modal distribution? I ran the dip.test in R (...
1
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1answer
25 views

Recommendation about what statistical test to use?

Ik have a problem in determining the right statistical test for my research. First I will give some background information. I want to research the impact of IFRS(regulatory change) on audit fees(fees ...
0
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0answers
29 views

Is the stationarity condition necessary for estimating logit/probit model?

I'm going to estimate both a logit and a probit model. Since both the models contain lagged explanatory variables, I want to know if the stationarity condition for this variables has to be verified. ...
1
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0answers
42 views

Elastic/ridge/lasso analysis, what then?

I'm getting really interested in the elastic net procedure for predictor shrinkage/selection. It seems very powerful. But from the scientific point of view I don't know well what to do once I got the ...
2
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1answer
52 views

Non-robustness of parametric statistics

Why is parametric test considered to be non-robust ? Or, why is parametric test not considered to be robust?
2
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1answer
58 views

Calculating the “critical value” for F test

I'm following along here: http://reliawiki.org/index.php/Multiple_Linear_Regression_Analysis#Calculation_of_the_Statistic I've successfully made all of the calculations up to $f_0=211.9$. Now I need ...