But there could be a third variable ( Z ) that influences ( Y ), and X might not be the true cause at all.

When a third variable is involved and has not been controlled for, the relation is said to be a zero order relationship.

For example, is a polynomial, but is not, because its second term involves division by the variable x ( 4 / x ), and also because its third term contains an exponent that is not a non-negative integer ( 3 / 2 ).

In the third schematic, the probe and restriction enzyme are chosen to detect a region of the genome that includes a variable VNTR segment ( boxes ).

The skewness of a random variable X is the third standardized moment, denoted γ < sub > 1 </ sub > and defined as

This helps to avoid false inferences of causality due to the presence of a third, underlying, variable that influences both the potentially causative variable and the potentially caused variable: its effect on the potentially caused variable is captured by directly including it in the regression, so that effect will not be picked up as an indirect effect through the potentially causative variable of interest.

This suggests a possible " third variable " problem, however, when three such closely related measures are found, it further suggests that each may have bidirectional tendencies ( see " bidirectional variable ," above ), being a cluster of correlated values each influencing one another to some extent.

Spurious correlation due to mutual influence from a third, common, causative variable, is harder to avoid: the model must be specified such that there is a theoretical reason to believe that no such underlying causative variable has been omitted from the model ; in particular, underlying time trends of both the dependent variable and the independent ( potentially causative ) variable must be controlled for by including time as another independent variable.

In this form, public capital has a direct influence on productivity as a third variable.

For simple 3-d spirals, a third variable, h ( height ), is also a continuous, monotonic function of θ.

Other classes of supply must consider a third variable besides usage and quantity: time.

# If a mass is present, the incision is made over the mass ; otherwise, the incision is made over McBurney's point, one third of the way from the anterior superior iliac spine ( ASIS ) and the umbilicus ; this represents the position of the base of the appendix ( the position of the tip is variable ).

* A bubble chart is a two-dimensional scatterplot where a third variable is represented by the size of the points.

For instance, if the polarization of two of the photons are measured and determined to be rotated + 45 ° from horizontal, then local hidden variable theory predicts that the polarization of the third photon will also be + 45 ° from horizontal.

Income levels and educational attainment are identified as having the largest explanatory power to explain ICT access and usage, with age being a third important variable, which means that prototypical " victims " to the digital divide can be foremost characterized as poorer, less educated, and older.

A third, one of at least equal and perhaps even greater importance, is now being traversed: American immersion and involvement in world affairs.

Indeed, it is probable that this point is reached the moment the third level of change begins.

A third idea is that artistic literature serves to reduce emotional conflicts, giving a sense of serenity and calm to individuals.

That is, there was no trace of Anglo-Saxons in Britain as early as the late third century, to which time the archaeological evidence for the erection of the Saxon Shore forts was beginning to point.

The third Act of Faust 2, is a formal celebration of the union between the Germanic and the classic, between the spirit of Euripides and that of romantic drama.

Mr. Wagner might or might not be a `` new '' Mayor in this third term, now that he is free of the pressure of those party leaders whom he calls `` bosses ''.

In the third Push-Pull Super-Set the `` push '' exercise is the widegrip Pushup Between Bars, while the `` pull '' exercise is the Moon Bench Lateral Raise with bent arms.

This is the third time in 28 years of Junior Showmanship at Westminster that a lady Handler has judged the Class.

Called the Marmara Gazinosu, it is on the third floor, with signs pointing the way there, and has a terrace overlooking the Sea of Marmara.

The expectation is that first-level supervisors will be selected in approximately equal numbers from the second and third engineering level, with very few coming from the first level.

With detectors sensitive to three mass intervals and based on a few counts, the second and third Russian space probes indicate that the flux of the smallest particles detected is less than that of larger ones.

if a substantial fraction of the dust is orbiting about the Earth, only about one third the above-mentioned average velocity should be used in deriving the mass.

Bernard Heuvelmans also treats of the largest snakes, but on the third level, and is chiefly concerned with the anaconda.

In the third category the function is double-valued in this interval.

Failure confirms the threat, and the intensity of anxiety is increased as the required learning becomes more difficult, so that by the time the child reaches the third grade the decrement in performance is pronounced.

To want to change is the third step.

A third situation is possible.

The third need is for better theory.

A third explanation is suggested by Richardson's analysis of Sukuma tone.

A third aspect, and probably the one open to most controversy, is the results of the election.

) has amounted to about one third of those total revenue requirements which the carload freight business is supposed to be called upon to meet.

I come now to a third argument, which again is very simple.

The climax of the third book is the account of the Council of Whitby, traditionally seen as a major turning point in English history.

During his tenure the game avoided a third work stoppage in 2002, and has seen the implementation of interleague play.

The relation he there gives of the miracle is as follows: " On the nones ( or 7th ) of May, about the third hour, ( or nine in the morning ,) a vast luminous body, in the form of a cross, appeared in the heavens, just over the holy Golgotha, reaching as far as the holy mount of Olivet, ( that is, almost two English miles in length ,) seen not by one or two persons, but clearly and evidently by the whole city.

If objects are seen as moving within a rotating frame, this movement results in another fictitious force, the Coriolis force ; and if the rate of rotation of the frame is changing, a third fictitious force, the Euler force is experienced.

After ten weeks nearly 17. 5 million people had seen the film in France, Intouchables was the second most-seen French movie of all-time in France, and the third including foreign movies.

The horror film style has changed over time, but in 1996 Scream set off a " chain of copycats ", leading to a new variety of teenage, horror movies .< ref name = Stack > This new approach to horror films began to gradually earn more and more income as seen in the progress of Scream movies ; the first movie earned six million and the third movie earned one-hundred and one million.

The original type was the arched harp as seen at Choghâ Miš and on later third millennium seals ( fig.

Other changes can be seen, however ; the Russian ruble, for example, changed from RUR to RUB, where the B comes from the third letter in the word " ruble ".

Paul Maier states that the first case is generally seen as hopeless, given that a Jew, Josephus would not have claimed Jesus as the Messiah, and that the second option is hardly tenable given the presence of the reference in all Greek manuscripts ; thus a large majority of modern scholars accept the third alternative, i. e. partial authenticity.

Indicating in 2001 that he would not run for a third term, Chissano criticized leaders who stayed on longer than he had, which was generally seen as a reference to Zambian president Frederick Chiluba, who at the time was considering a third term, and Zimbabwean president Robert Mugabe, then in his fourth term.

Despite gaining initially low audience ratings, by the third series, One Foot in the Grave was making the Top 20 ratings, with some episodes seen by more than 16 million viewers.

The third sultan was said to be part Arab, who are seen in South and Southeast Asia as the descendents of Muhammad.

Three hundred years later, the American astronomical historian William Ashworth suggested that what Flamsteed may have seen was the most recent supernova in the galaxy's history, an event which would leave as its remnant the strongest radio source outside of the solar system, known in the third Cambridge ( 3C ) catalogue as 3C 461 and commonly called Cassiopeia A by astronomers.

Tubeway Army's third single, the dark-themed and slow-paced " Down in the Park " ( 1979 ) also failed to chart but it would prove to be one of Numan's most enduring and oft-covered songs ; it was featured with other contemporary hits on the soundtrack for the movie Times Square, and a live version of the song can be seen in the movie Urgh!

For example, " 1P / 1982 U1, 1986 III, 1982i " indicates that for the perihelion in 1986, Halley's Comet was the first period comet known ( designated 1P ) and this apparition was the first seen in " half-month " U ( the first half of November ) in 1982 ( giving 1P / 1982 U1 ); it was the third comet past perihelion in 1986 ( 1986 III ); and it was the ninth comet spotted in 1982 ( provisional designation 1982i ).

Some political philosophers, such as Martin Cohen, have seen in Maoism an attempt to combine Confucianism and Socialism-what one such called ' a third way between communism and capitalism '.

The third Charterhouse built in Britain was Beauvale Charterhouse remains of which can still be seen in Beauvale, Greasley parish, Nottinghamshire.

This type of construction can also be seen as an effort by printer manufacturers to stem third party ink cartridge assembly replacements, as these would-be suppliers don't have the ability to manufacture specialized print heads.

The growth of the series has seen motorsport equal Rugby League as Australia's third most watched sport.

A third variant of DOCSIS was developed in Japan and has seen limited deployment in that country.

Often there a third character is included at the destination to add further suspicion to the girl's existence by informing the driver that they haven't seen anyone all night.

Knot patterns first appeared in the third and fourth centuries AD and can be seen in Roman floor mosaics of that time.

The second and third criteria are seen as ensuring protection from unjust discrimination based on a perception of risk, just because someone has a record of impairment or appears to have a disability or illness ( e. g. features which may be erroneously taken as signs of an illness ).