# correlation

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Related to correlation matrix: Covariance matrix

## coefficient

[ko″ĕ-fish´ent]**1.**an expression of the change or effect produced by the variation in certain variables, or of the ratio between two different quantities.

**2.**in chemistry, a number or figure put before a chemical formula to indicate how many times the formula is to be multiplied.

**absorption coefficient**absorptivity.

**Bunsen coefficient**the number of milliliters of gas dissolved in a milliliter of liquid at atmospheric pressure (760 mm Hg) and a specified temperature. Symbol, α.

**confidence coefficient**the probability that a confidence interval will contain the true value of the population parameter. For example, if the confidence coefficient is 0.95, 95 per cent of the confidence intervals so calculated for a large number of random samples would contain the parameter.

**correlation coefficient**a numerical value that indicates the degree and direction of relationship between two variables; the coefficients range in value from +1.00 (perfect positive relationship) to 0.00 (no relationship) to −1.00 (perfect negative or inverse relationship).

**diffusion coefficient**see diffusion coefficient.

**coefficient of digestibility**the proportion of a food that is digested compared to what is absorbed, expressed as a percentage.

**dilution coefficient**a number that expresses the effectiveness of a disinfectant for a given organism. It is calculated by the equation

*tc*=

^{n}*k*, where

*t*is the time required for killing all organisms,

*c*is the concentration of disinfectant,

*n*is the dilution coefficient, and

*k*is a constant. A low coefficient indicates the disinfectant is effective at a low concentration.

**linear absorption coefficient**the fraction of a beam of radiation absorbed per unit thickness of absorber.

**mass absorption coefficient**the linear absorption coefficient divided by the density of the absorber.

**phenol coefficient**see phenol coefficient.

**sedimentation coefficient**the velocity at which a particle sediments in a centrifuge divided by the applied centrifugal field, the result having units of time (velocity divided by acceleration), usually expressed in Svedberg units (S), which equal 10

^{−13}second. Sedimentation coefficients are used to characterize the size of macromolecules; they increase with increasing mass and density and are higher for globular than for fibrous particles.

## cor·re·la·tion

(kōr'ĕ-lā'shŭn),**1.**The mutual or reciprocal relation of two or more items or parts.

**2.**The act of bringing into such a relation.

**3.**The degree to which variables change together.

## correlation

/cor·re·la·tion/ (kor″ĕ-la´shun) in statistics, the degree and direction of association of variable phenomena; how well one can be predicted from the other.## correlation

[kôr′əlā′shən]

Etymology: L,

*com*+*relatio,*a carrying back(in statistics) a relationship between variables that may be negative (inverse), positive, or curvilinear. Correlation is measured and expressed by using numeric scales.

## correlation

The degree to which two or more variables are related in some fashion. A linear relationship between variables can be measured with Pearson's correlation or Spearman's rho.Correlation may not mean causation.

## correlation

Statistics The degree to which an event, factor, phenomenon, or variable is associated with, related to, or can be predicted from another; the degree to which a linear relationship exists between variables, measured by a correlation coefficient. See Cervical biopsy-cytology correlation, Clinical correlation, Correlation coefficient, Intertemporal correlation, Pearson correlation, Rank correlation.## correlation

The degree to which changes in variables reflect, or fail to reflect one another. Correlations are said to be positive when the variables change in the same direction and negative when they move in opposite directions. A common fault in statistics is to assume that correlations are significant when they are not, that is, to assume unjustifiably that changes in variables are causally related.## correlation

a statistical association between two variables, calculated as the correlation coefficient*r*. The coefficient can range from

*r*= 1.0 (a perfect positive correlation) to

*r*= -1.0 (a perfect negative correlation), with an

*r*value of 0 indicating no relationship between the two variables. Height and weight in humans are positively correlated (as values for height increase so do values for weight), whereas other variables give a negative correlation, e.g. as human age increases so mental agility tends to decrease.

## cor·re·la·tion

(kōr'ĕ-lā'shŭn)**1.**The mutual or reciprocal relation of two or more items or parts.

**2.**The act of bringing into such a relation.

**3.**The degree to which variables change together.

## correlation,

*n*a statistical procedure used to determine the degree to which two (or more) variables vary together. Correlation does not suggest a cause-effect relationship but only the degree of parallelism or concomitance between the variables, the cause of which may be unknown. The

*Pearson product-moment correlation (r)*is the most frequently used, and this coefficient is used unless another is specified.

**correlation, coefficient number**

*n*the result of statistical computation that indicates the strength of the tendency of two or more variables to vary concomitantly. The coefficient is expressed in fractions (that is, r = 80), ranging from 21 to 11, and indicates the magnitude of the relationship between the variables. Perfect direct correspondence is expressed by 11; perfect inverse correspondence by 21; complete lack of correspondence by 0. Fractional values are not read as percents.

**correlation, linear**,

*n*a correlation in which the regression line, the line that best describes the relationship between the two variables, is a straight line, so that for any increase in the magnitude of one variable there will be a proportional change in the magnitude of the other variable.

**correlation, multiple**,

*n*a complex correlation procedure in which scores on two or more variables are combined to predict scores on another variable, called the

*dependent variable.*

## correlation

1. in neurology, the union of afferent impulses within a nerve center to bring about an appropriate response.

2. the degree to which statistical variables vary together.

**correlation coefficient**

see correlation coefficient.

## Patient discussion about correlation

**Q. I have chronic hayfever problems in the mornings for the first hour.Seems to be a correlation with dairy produ** I also got asthma 8 years ago at age 69, after having 2 pet cats. It is controlled with 2 puffs of Symbicord daily, am & pm.
Anyone managed a complete cure?

**A.**Hey lixuri,you mean to tell me after after 25yrs as a therapist,All my patients had to do is drink water all day.i love it,how long does it take to work,an what does the patient do in the mean time if they have a asthmatic attack(drink WAter while you cant breath?-PLEASE SEND ME AN AANSWER.---mrfoot56.

**Q. What correlation is there between Diet and Fitness? do i attain those two in a similar way? do i have to ** attain one in order to complete/gain the other ?

**A.**agree with dominicus. if you want to be healthier, you should keep your eye on what you eat and how often/how regular you do the exercise.

the result will be best if you can combine those two in balance portion and in healthy and wise manner.

Good luck, and stay healthy always..