Questions tagged [frequency]
The frequency measures the number of times an event occurs in a data set.
3
votes
0answers
14 views
Granger causality tests when series are measured at different frequencies
As a research exercise I should perform Granger causality tests on pairs of national series (one describing output gap and the other an index of consumers' confidence).
However, I face a situation ...
0
votes
0answers
12 views
How to orthoganalize two correlated variables of which one has a monthly frequency and the other has a yearly frequency? [closed]
I am working with firm level sentiment data measured with text analysis. I am trying to understand the relation between the sentiment and some economic decisions taken by firms, such as acquisitions. ...
-1
votes
0answers
10 views
Yearly frequency of two simultaneous events
As part of a risk analysis i'm trying to estimate the yearly frequency of a small room beeing occupied when the fire alarm is activated. If the alarm sounds, no one will enter the room.
The room is ...
0
votes
0answers
18 views
Estimate frequency based on given sample
I have a list of users (~25 million) and a dataset containing events created by the users in a specific time window (eg all tweets of all Twitter users that happened in a month - on avg I have 100K ...
0
votes
1answer
12 views
Testing an intervention by repeated measure of opinion before and after the intervention
How can we test the null hypothesis that an intervention has no effect on opinions for 44 people. These opinions were measured as frequencies in 3 categories (A, B, C) before and after the ...
0
votes
1answer
32 views
How to choose the frequency value without know the seasonality of the data in R ts() package
I am trying to analyze the S$P 500 data on Kaggle.
I have a daily values of the opening stock prices.
As frequency is the number of observations taken in a cycle, I am guessing I need to know the ...
0
votes
0answers
36 views
change in frequency of time series data
I am working on a survey data which is quarterly from 2008 to 2014 and it becomes bi-monthly 2014 onwards. Can someone please suggest how to tackle this data? It is not possible to interpolate due to ...
0
votes
0answers
25 views
Preprocessing of time series data to spectral analysis
If we want to find the periodicities of a time series, we can use spectral analysis. We can plot the the periodogram and find the major component, then we can find the major periods. But to do this, ...
0
votes
1answer
16 views
How to test normalized frequencies
I have extracted the frequency of two words (can, may) from two corpora (Corpus1, Corpus2).
I want to test if there is a significant difference between the counts in the two corpora, but since the ...
1
vote
0answers
28 views
Statistical analysis for quasi-experiments
This is my first message on this forum. I hope I am not doing any mistake.
I must analyze data obtained after a quasi-experiment and I am not sure how to proceed. The experiment has been carried out ...
0
votes
1answer
26 views
Which statistical test should be used for several samples frequency distributions?
I have the frequency distribution of muscle fiber size from several control and several problem animals and I'd like to compare both groups, but all the statistical tests I know for frequency ...
0
votes
0answers
11 views
How to do an equidistribution test? [duplicate]
Suppose I have a sample of $N$ numbers $a_1,\dots,a_N$ from $1,\dots,k$. How can I test whether they are equidistributed?
I'm not interested in a full randomness test as the order does not matter to ...
2
votes
1answer
113 views
What time-series frequency should I use? Weekly, monthly, quarterly
First, I read the Q&As here, but it's not entirely clear for me what to do given my situation.
I have more than 1700 different time series, each expressed as weekly data. My objective is to ...
1
vote
0answers
42 views
Should I use weekly or daily returns for modelling FX returns?
I am currently modelling Foreingn Exchange returns using a GARCH model. I am simulating returns 1-year forward. Would it be better to use weekly or daily data on Foreign Exchange returns? Weekly data ...
1
vote
1answer
17 views
How can I use the distribution of run lengths to test if a sequence is generated from flips of a fair coin?
I have a very long sequence (in the tens of thousands) of binary outcomes from some data-generating process. I believe that these outcomes are iid Bernoulli trials with p = 0.5, equivalent to flipping ...
0
votes
0answers
25 views
Class frequency comparison (exponential distribution)
I have two different sources of data and I would like to check if their class distributions are similar and how much.
The first dataset ($D_1$) has 2M samples and the second ($D_2$) 6M.
When I ...
0
votes
0answers
33 views
Can VAR models capture all frequency interactions reliably and to the same extent?
I would like to assess how a set of ~50-100 time-series variables causally interact with each other. To do this, I am fitting a VAR model and using cross-validation to estimate model-order. After the ...
1
vote
1answer
42 views
Specifying frequency parameter in the absence of occurrences
Let's say I have a process where the occurrences are independent, proportional to time. I made $n$ observations for which I only observed no occurrences. My goal is to define a frequency parameter and ...
0
votes
0answers
8 views
analyzing hierarchically grouped (selection) frequency data
I have a question regarding analyzing hierarchically grouped selection frequency data. (Disclaimer: I have never analyzed this type of data before. I did not think through the data analysis procedure (...
0
votes
1answer
55 views
Regression with frequency rating in percent as dv
I seem to have a similar issue as asked in this thread, nevertheless I'm still clueless about what model I have to fit to my data.
I conducted a repeated measure experiment (consisting of 2 sessions) ...
0
votes
1answer
41 views
Count frequency distribution of monomial
If you sample $N$ times from a set of $n$ objects with replacement and then plot the frequency against the count (i.e. the number of times an object has been chosen once, twice,...), you get a ...
0
votes
1answer
12 views
Find out which characteristics to choose, based on the frequency measurement of characteristics of similar items
I have this statistics oriented question and I need some input on the approach. There is a new product introduced, a contact lence that has seleral ranges of attributes (powers) from which the users ...
0
votes
1answer
65 views
What is the correct distribution? [closed]
Let, I have the following Frequency Distribution:
Which one would be the correct Grouped frequency Table if class-width = $1.0$?
$Table\#1$
$Table\#2$
Explain "Why".
What would be the answer if $\...
0
votes
1answer
19 views
Calculating effect sizes when a certain proportion of subjects give one of four answers
How can an effect size be calculated between two groups when the data is reported in frequency proportions (e.g., each group has people who have answered a question about relationships with either: ...
0
votes
1answer
34 views
Expected vs observed frequency of two events at the same time
I'll first give an example and afterwards a more formal definition of my problem.
Example:
Let's assume I'm looking at balls with two properties: their color can be black or white, their weight ...
0
votes
1answer
237 views
What is the difference of frequency and probability of occurrence?
I'm reading lots of statistical anomaly detection articles nowadays. Some of them use frequency of some feature for detecting anomalies on the new trace.
But, something gets my attention in some ...
4
votes
2answers
224 views
Is it possible to obtain more accurate annual extremes predictions from sub-annual data?
I'm looking at various extreme climate variables, such as 50-year or 500-year maximum daily precipitation, using a generalized extreme value (GEV) distribution. The problem with this is that there are ...
3
votes
3answers
93 views
Distribution of *conditional* frequencies when frequencies follow a Dirichlet distribution
Context: we have a large number of individuals characterized by two binary traits; call these $T$ with values $\{0,1\}$, and $T'$ with values $\{0',1'\}$. So there are four types of individuals: $00'$,...
1
vote
0answers
32 views
Fisher's exact test with opposite direction of categories for two groups
I would like to analyze student performance under two teaching approaches for two classes. We predict that class 1 would outperform class 2 and ideally the performance between two classes should be ...
1
vote
0answers
30 views
How to analyze the frequency of correct/ non-correct answers
I have a question about how to analyze some data. It involves the performance of two equally sized groups in a questionary with 30 arithmetic questions that I scored with two possible outcomes (...
0
votes
1answer
12 views
Statistical test for comparing two frequencies with R [duplicate]
i have this situation. A set of 5000 objects, 4950 blue and 50 green. From this set two people (person A and person B) fish separately 100 objects each and i would like to know if one of the two ...
2
votes
2answers
80 views
What kind of frequency distribution is this?
I have a discrete frequency distribution, that looks like this
I am trying to find what type of distribution is it?
I looked at many models but it does not seem to comply with any.
I have 345 ...
1
vote
0answers
34 views
calculating sample size needed for a target confidence interval from categorical data
So I will have data sorted into one of five bins (flow cytometry sorting of cells). These bins are actually adjacent categories that quantify a single fluorscence level (0-20,20-40,40-60,60-80,80-100)....
0
votes
1answer
32 views
How to approach cipher decoding using frequency analysis
so I'm working on a project where I'm trying to decipher an input text using frequency analysis. So far I've added first letter frequencies, common bigrams, double letter frequencies, as well as ...
0
votes
0answers
16 views
comparing multiple groups by frequency
I have three columns:
first one is the number of innovations by handicapped students,
the second column is the number of handicapped students in a class of a school, and
the third column is the total ...
3
votes
1answer
130 views
Why is “using counts of a frequency table as data” for a histogram a “mistake”?
The textbook, The Practice of Statistics, states the following as a "common mistake" when making histograms:
Don't use counts (in a frequency table) or percents (in a relative frequency table) as ...
0
votes
0answers
12 views
How to find the frequency at which loudness levels are varying the most?
I have a dataset consisting of loudness level readings of the sound produced at a national highway, taken on a per second basis at different frequencies(20Hz to 10,000Hz). I have to find out the ...
0
votes
0answers
34 views
“distance” between two histograms (frequency counts) of ordinal data (Likert scale)
I've got a bunch of survey questions that use a 5-level likert scale for the response. (Strongly disagree, Somewhat disagree, Neither agree or disagree, Somewhat agree, Strongly agree).
I can take ...
0
votes
0answers
47 views
Features selection for mixed frequency model
I have dependent variable on quarterly basis and independent variables on monthly basis. I use Midas approach, so I arrange independent variables into quarters.
Let's assume I have two independent ...
1
vote
0answers
22 views
Relative frequency question
I am a new user here, and I need some help getting started with the following question:
The textbook answers are a. $19$ and b. $20$. How do I begin this question? I am a beginner in statistics. :)
...
0
votes
0answers
11 views
How does frequency/proportion compare to L2 normalized count
If I have a list like the following:
[1, 3, 1, 2, 1, 1, 2, 3, 1]
and
[1, 3, 1, 1, 1, 1, 3, 2, 3]
Though a lot longer and a lot more unique elements
How does L2 normalization of the count vector (...
1
vote
0answers
26 views
How to analyze size frequency data from over 70 sites
When I started my PhD, I had virtually no prep-time. My advisor needed me in the field and told me to go grab samples. As such, my planning wasn't the best, so sorry if this is a completely terrible ...
0
votes
2answers
810 views
How to transform a frequency data in to normal distribution?
I have this set of data:
0 700
1 350
2 250
3 300
4 150
5 145
6 150
7 147
being the first column about the type of the event (zero days, onde day, ...
1
vote
0answers
65 views
Estimating standard deviation from cumulative frequency table
I've been provided with some data in the form of a cumulative frequency table, where each value is exceeded a qiven percentage of the time, so for 99% of the time the readings exceed 163 and for 1% of ...
0
votes
0answers
50 views
What kind of statistical test should/could I perform in this set of data to detect an increase in email usage?
What kind of statistical test should/could I perform on this set of data ?
Its done on the same group of 50 people before and after intervention.
Any possible tests that could be done with this data ...
3
votes
1answer
43 views
0
votes
2answers
357 views
Find most common combination in binary data set in R? [closed]
I have a dataset with 7 variables all binary.
I summed them across rows
var8<- (x1+x2+x3+x4+x5+x6+x7)
which gave me a vector of values 1:7
I then used the table functions to find the frequency ...
1
vote
1answer
80 views
How to create a frequency table?
I am supposed to create a frequency table to describe the data using 4 measures:
Raw frequency
Cumulative raw frequency
Relative frequency
Cumulative percentage
I don't understand what these mean, ...
1
vote
1answer
26 views
How to tell from SAS frequency distribution that something is off about my data?
For example, I have 3 questions asking about the quality of a restaurant's services. Each question asks diners to rate from 1 to 5, where 1 indicates the worst quality and 5 indicates the best quality....
1
vote
2answers
30 views
Frequency of an event at a given time, from a list of times of occurrence
I have data in the following format:
[$t_1, t_2, t_3, \dots, t_n$] - which is a list of times at which an event has occurred during a day
They are in minutes within 24 hours and limited by $t_{\text ...
