What is Data: Definition and 998 Discussions

Data are units of information, often numeric, that are collected through observation. In a more technical sense, data are a set of values of qualitative or quantitative variables about one or more persons or objects, while a datum (singular of data) is a single value of a single variable.Although the terms "data" and "information" are often used interchangeably, these terms have distinct meanings. In some popular publications, data are sometimes said to be transformed into information when they are viewed in context or in post-analysis. However, in academic treatments of the subject data are simply units of information. Data are used in scientific research, businesses management (e.g., sales data, revenue, profits, stock price), finance, governance (e.g., crime rates, unemployment rates, literacy rates), and in virtually every other form of human organizational activity (e.g., censuses of the number of homeless people by non-profit organizations).
Data are measured, collected and reported, and analyzed, and from data visualizations such as graphs, tables or images are produced. Data as a general concept refers to the fact that some existing information or knowledge is represented or coded in some form suitable for better usage or processing. Raw data ("unprocessed data") is a collection of numbers or characters before it has been "cleaned" and corrected by researchers. Raw data needs to be corrected to remove outliers or obvious instrument or data entry errors (e.g., a thermometer reading from an outdoor Arctic location recording a tropical temperature). Data processing commonly occurs by stages, and the "processed data" from one stage may be considered the "raw data" of the next stage. Field data is raw data that is collected in an uncontrolled "in situ" environment. Experimental data is data that is generated within the context of a scientific investigation by observation and recording.
Data has been described as the new oil of the digital economy.

View More On Wikipedia.org
Recent contents Top users
  1. M

    Profit / loss trading calculator for share market historical data

    Homework Statement Share market trading calculator. I have tried to write code to calculate the buy and sell with profit/loss on historical data using moving averages. I'm am not interested in leverage yet. bank = 10000 equity = 10000 sell = is current price of an instrument on the...
  2. P

    How to search a data frame by x and y cords in R

    Hi Readers, I seem to have hit an elementary snag while fiddling in R... i have a 5x5m surface interpolated at intervals of 0.01... giving 250,000 squares in my grid. i have roughly 20-30 xy cords where i want to retrieve the z value out of the data frame. does anyone know how to search an x y...
  3. Z

    Interpolating Data with the Discrete Fourier Transform

    Hello everyone: I have some question using the FFT in MATLAB for data interpolating. I don't know what the relation between the normal Fourier series and the real, image number. For example, given a set of measurement data, I can use the curve fitting toolbox to fit a curve. The general...
  4. marellasunny

    Testing for chaos in data(method by Doyne Farmer for 3D discrete data)

    Testing for chaos in data I have data for 3 variables ,each with respect to the discrete time values. How do I check for the existence of chaos for this discrete 3D system?(I don't have the analytic eqs.,just the data.) MY IDEAS ON CHECKING FOR CHAOS FROM DATA:(which of these are feasible...
  5. Q

    MATLAB Fit data with function in MATLAB

    Dear users I have some points with coordinate x and y forexample : x=[1 2 3 4] and y=[2 4 6 8] and then I want to fit these 4 pair of points with some function for example y=a*x+b (here I know that the answer is a=2 and b=0) what should I...
  6. X

    Should I Normalize My Data for Host Ranking?

    I have 2 measures that I am using to rank terms that I get them by prediction (using linear regression). They are the time to transmit X bytes and the time to compute the X bytes. I do the prediction if I execute in host A, B, and C. I add the 2 measures and rank the hosts. I think adding these...
  7. M

    Weighting calculation to convert weather data from 6 stations into one

    I currently have hard-coded in my forecasting model, 6 weightings (totaling 100%) for 6 weather stations and wish to determine a methodology to produce these weighting or conversion factors % to form an artificial single weather station. This is part of forecasting the electricity load in my...
  8. N

    How to analyse the difference between physical and calculated data?

    Hi I am not sure what method to use when analysing the difference in values between physical measured data and modeled data. This is to do with measuring the energy deposited at a point in water from a beam of photons. I have a set of physical measurements obtained whilst varying the...
  9. stripes

    Plotting data in Mathematica certain colours depending on

    Homework Statement I have a list of data in .csv format that looks like the following: 10 5 TRUE 10.1 5.1 TRUE 10.2 5.2 FALSE 10.3 5.3 FALSE 10.4 5.4 FALSE 10.5 5.5 TRUE 10.6 5.6 TRUE ... There are thousands of entries...
  10. A

    Why insertion sort works better than quick-sort for small data?

    I have seen in books that when number of elements is small ~ 30-40 insertion sort is recommended. Why is that? The worst case of insertion sort is n2 whereas for quick-sort it is nlogn. nlogn beats n2 for all values of n isn't it? Then why?
  11. P

    MATLAB Organizing & Extracting Data from a Large Array

    Hello there, Let's say I have the following array: (what interests me in the array is the first column) 1 5 9 1 4 9 1 8 9 1 9 6 2 5 6 2 4 8 2 4 7 2 6 9 2 3 0 2 0 4 3 5 8 3 4 8 3 9 8 4 8 5 4 8 9 4 8 5 4 3 9 4 8 7 5 8 9 5 8 9 5 4 8 5 7 8 5 6 2 ... and so on...
  12. R

    Statistical significance in experimentally obtained data sets

    I have a set of data that was recorded from an engine that we are testing. We've noticed lately that a particular pressure value will sometimes spike with no apparent explanation, as seen in the attached graph. The pressure in question is passively regulated by a pump, but it is also dependent...
  13. R

    Converting data to a specified range

    Hi, I am trying to convert data to a particular range of 0-10. Actual Data may vary from - 50000 - 26214400. I have broken this down into 4 parts as follows - 50000 - 1048576 -----> 0 - 2.5 1048577 - 5242880 -----> 2.6 - 5 5242881 - 15728640 ----->5.1 - 7.5 15728641 - 26214400...
  14. LydiaAC

    Get P-V-T Data for Water - Where to Find?

    I would like to have P-V-T data for water in order to enter them in an Excel spreadsheet and design some exercises for the students to plot different kind of diagrams using the same data. I can generate the data using some suitable model, but I think that having real experimental data would be...
  15. H

    1st order transfer function from data

    Hello, Im trying to model an RF attenuator for use in a control system. The control voltage is from 0-2.1V and I applied a step function signal from 0-2.1V and measured the output. I was able to model it as a first order system in the form Kdc / Xs + 1. The issue I'm having is...
  16. P

    Topological Data Analysis - Persistent Homology

    Hi, I am not a mathematician, but I have noticed some recent papers on this seemingly new field, called Topological Data Analysis (see this relevant paper). I have had an overview of the applications and it seems that when you have data points that were sampled from some source (e.g. an...
  17. U

    Finding f(x) from Given Data and Derivative: A Scientific Approach

    Homework Statement If f(x/y) = f(x)/f(y) f(y)≠0 and f'(1)=2 find f(x). Homework Equations The Attempt at a Solution Diff both sides wrt x f'(x/y)*1/y=f'(x)/f(y) putting x=1 f'(1/y)*1/y=2/f(y)
  18. V

    Dereddening of WISE+2MASS data

    Hello friends, I was trying to plot the color-color diagram of a particular open cluster using WISE+2MASS data. You can get more details of the diagram from the following paper that i am attaching.[Koenig et.al - Wide Field Infrared Survey Explorer Observations of the evolution of the massive...
  19. G

    Using piezoelectricity for data transmission.

    I am starting my 3rd year in September and I've decided to start thinking about research topics early. I'm quite interested in piezoelectricity along with it's discovered and perhaps undiscovered applications. This is my first idea; I have watched a lot of nature programs and I have seen that...
  20. S

    Possible function y=f(x) if data points are given.

    How could one obtain a function y=f(x) that satisfies a number of data points (x_{i},y_{i}). That is how would it be possible to get a function if some points that are to lie on it have been given? I've seen some lectures on interpolation but all I've gotten is only the way to solve problems...
  21. A

    How to interpolate big data with small deviation?

    Hi, I've got a problem. There is over 9 milions points in my .txt. I have to find polynom for surface of this points with deviation smaller then 0.01 (x [-3:3], y[-3,3], z [-9,9]). I try many functions in Matlab, but no answer. Thank for help. B
  22. marcus

    Criteria for causal independence (new paper, Planck data)

    I don't know whether this has much general interest. I am interested by communication horizons in cosmology, or causal horizons if you prefer. This paper claims to study several cases including how far apart two quasars would have to be to have been out of contact ever since the end of the...
  23. P

    Rolling motion- experimental data differs from expectation

    Homework Statement An experiment was done to test the validity of the equation a = 2/3 g sin∅ for a rolling cylinder. A hockey puck was rolled down a wooden ramp at 5 different inclination angles, and the time it took to roll down the length of the board was recorded. ∅ was found using...
  24. S

    Animating Solar System Evolution from Real Physics Data

    I've recently been assigned a project by one of my professors to animate a solar system style disc using real data computed from a simulation of his, and I'm wondering what the best angle of approach for this project would be. I have some experience in Cinema4D animating things, and I'm...
  25. C

    Hot Dog Data Analysis: Exploring Sodium and Calorie Content by Type

    Homework Statement I'm doing a final project for my probability and statistics class that involves analyzing data on the sodium (mg/hot dog) and calories contained in each of 54 major hot dog brands. The hot dogs are classified by type: beef, poultry, and meat (mostly pork and beef). 20...
  26. S

    Vector Magic and Naming Conventions for Fortran

    I have just about finished this program, I only need to calculate my velocity. I think that this velocity should be calculated by taking the value from the 4th column of my data set here:https://docs.google.com/file/d/0BzuDEPd26OcheVhiWlZ3STlZU0k/edit?usp=sharing which have called ivar_3 and...
  27. L

    Data of Engine PW4060 PW123D and PW127E

    Hello! My name is Luis Trindade and I am a Aeronautic Engineering student. I am doing a comparative study on aircraft performance, but I lack data on some of the aircraft. These data refer to the engines. Needed to know the fuel consumption in cruise and traction on the cruise of the...
  28. wolf1728

    Mass Luminosity relation doesn't hold true when applied to actual data

    I see there have been many postings about this topic in this forum. The formula for this relation is Luminosity = Mass^3.5 Taking logs of both sides we get log (lum) = 3.5 * log (mass) and using a little algebra we find that the exponent (3.5) should equal log (lum) ÷ log (mass) I have...
  29. G

    MATLAB Extract and rearrange data in Matlab

    Hi all, I need to rearrange my data. I have an excel file with 12 columns and 2045 rows, which I transformed that into a .mat. I need to query my data rearranged as follows (cf. example matrix below): 1-sum all values of Col 3 if: a-they belong to a given value of Col 1 and to a...
  30. M

    Regression with uncertain data

    So I have this set of statistical data, which is not completely relevant to what I want to model, and I would like to compensate for that somehow since I do not have the more precise data. I have about 500 observations of average wages in certain areas which are modeled as dependent on several...
  31. M

    MHB Visualizing Data, Significance Level, T-test, Level of Measurement

    Hello. I was just wandering if anyone could help. I've been doing a couple of statistics questions, and when they ask for some questions, I am not sure if I have an appropriate understanding of what the right answer should be. I would really like to understand this material, so what I want to...
  32. djh101

    What could cause data to linearize at a higher power than it should?

    For our physics lab we found the magnetic field produced by a magnet at different distances. When graphing the data, it was supposed to produce a linear graph when we plot the field strength against 1/r3. However, my graph doesn't become linear until 1/r5 (however, it does linearize quite nicely...
  33. S

    Explore Properties of Semiconductors for CdS: Band Gap, Effective Mass & More

    Greetings everyone, I need a good source that lists various properties of semiconductors such as band gap energy, effective mass of holes and electrons. Do you have a recommendation I looked at ISSP by Kittel and various other books but except band gap energy I could not find much...
  34. MarkFL

    MHB M's question at Yahoo Answers regarding normally distributed data

    Here is the question: Here is a link to the question: Help with Z Score Problem? - Yahoo! Answers I have posted a link there to this topic so the OP can find my response.
  35. E

    Distribution of data - alternative presentation

    If we commonly draw a distribution of data, we should be careful to chose appropriate classes, for instance, 1-2, 4 2-3, 6 3-4, 11 etc. But, if we draw a cumulative distribution, classes are not necessary. For instance 1-2, 4 2-3, 10 3-4, 21 and still better: 1, 1 1.3, 2 1.4, 3 1.9, 4...
  36. Saladsamurai

    How to write a program to retrieve Web data

    Hello! :smile: So I have some basic programming skills, but I have never done anything that interacts with the web. Here at work, we have a website that we have to go to in order to check the statuses of all of the jobs we have open. The website is awful in that you cannot run a report on...
  37. I

    News NSA is collecting and storing all of your data

    William Binney resigned from the NSA because they were collecting all the data they could on US citizens and storing it permanently. https://www.youtube.com/watch?v=TuET0kpHoyM He did not trust them to use it responsibly and he went public. According to Glenn Greenwald, the NSA has refused...
  38. C

    Data Science and the need of programming?

    Hello. I have an undergraduate degree in CS and I'm beginning grad school to study AI and Machine Learning. I've spent a lot of time doing "software engineering" (dealing with design patterns, web development, QA, Agile processes, SQL, GUI development) and I'm really sick of it. I don't use...
  39. T

    Calculating the time constant for a variying data set

    I have a large data set consisting of varying magnitude over time in the form of sine+cos. I want to apply a high pass filter to the data, but I'm not sure how to calculate the time constant for the data. I produce a power spectrum of the data that i can visually inspect to figure out where i...
  40. D

    Instant data transmission idea

    As I understand, electrons cannot be on the exact same level as another one in the universe. If we could move one electron in one placed and somehow monitor another ones reaction - would it be possible to instantly transmit data anywhere in the universe?
  41. M

    Data repeatability (statistics question)

    Homework Statement I am trying to see if two sets of data represent the same values or not. I have: Mean1 = 9.3155, stdev1 = 0.1334; mean2 = 9.3040, stdev2 = 0.1248; N1 = N2 = 1000; I got these values from my data using MATLAB (std() and mean()); Homework Equations z =...
  42. M

    Comparing discrete data to a continuous model (1D)

    Say I have a model, y = f(x), and ten discrete data points to compare to this model, (x1, y1)...(x10,y10). The normal way would then be to take the residuals and square them to get a quality of fit, ie. average residuals squared = {[f(x1) - y1]^2 + ... + [f(x10) - y10]^2}/10 I also remember...
  43. P

    Can we apply non-linear smoothing to a linear looking like data ?

    My doubt is that whether we can apply non-linear smoothing to a almost linear data ( without one or 2 discontinuity) I have attached the pic in which the red data is the smoothed one. Blue is the original one. I multiplied each point with an increasing like 1, 1.1, 1.2, 1.3, 1.4...so on...
  44. L

    Data analysis: 2D Surface fitting from raw data

    Hey everybody I've got a question for the programming savvy. I'm generating data which can generally be described by.. f(x,y) = Ʃn(an * xn)*Ʃn(bn * yn) Basically what I'm looking at is a data set which shows a surface which looks like about 1/4th of a wonky bowl. My trouble is...
  45. H

    How to store data from an interrupt in C

    It's been a while since I've done some C programming and I can't remember how I should go about implementing this. I have a chunk of memory allocated for storing an array of data. The allocation takes place while the main program is running. The data is being stored to the already allocated...
  46. A

    An algorithm for data compression?

    An algorithm for data compression? I am coming from a philosophy and science background and I'm particularly interested in finding out what a generalised data compression algorithm would look like. (By algorithm I mean something like a flowchart that would show how this process could be...
  47. J

    How to get an entry level job in the Big Data industry?

    How to get an entry level job in the "Big Data" industry? I.e. developing algorithms and crunching numbers for Netflix, Twitter, etc.
  48. marellasunny

    Material on how to go from data to differential equation

    Is there any material or book that explains how one could go from data to differential equation comprehensively? More like functional data analysis+differential equations
  49. N

    Article on New Planck Satellite data

    Universe as an Infant: Fatter Than Expected and Kind of Lumpy http://www.nytimes.com/2013/03/22/science/space/planck-satellite-shows-image-of-infant-universe.html?nl=todaysheadlines&emc=edit_th_20130322the universe may be 13.8 B years old [a bit older than thought] and expanding more slowly...
  50. S

    Large Scale anomaly in Planck data

    Just watching tweets come out of the conference, apparently there is a large scale anomaly that has come out of PLanck . One tweet says challenge to inflation, another says could be pre big bang physics. Obvioulsy I am just reading tweets, so not sure what's real yet. But this could be exciting...
Back
Top