Z-Score Table | Formula | t table and z table
Astandardnormaltable (alsocalledtheunitnormaltableorz-scoretable) isamathematicaltableforthevaluesofϕ,indicatingthevaluesofthecumulativedistributionfunctionofthenormaldistribution[1].Z-Score,alsoknownasthestandardscore,indicateshowmanystandarddeviationsanentityis,fromthemean.Sinceprobabilitytablescannotbeprintedforeverynormaldistribution,asthereisaninfinitevarietyofnormaldistribution,itiscommonpracticetoconvertanormaltoastandardnormalandthenusethez-scoretabletofindprobabilities.Z-Score Formu...
A standard normal table (also called the unit normal table or z-score table) is a mathematical table for the values of ϕ, indicating the values of the cumulative distribution function of the normal distribution[1]. Z-Score, also known as the standard score, indicates how many standard deviations an entity is, from the mean.
Since probability tables cannot be printed for every normal distribution, as there is an infinite variety of normal distribution, it is common practice to convert a normal to a standard normal and then use the z-score table to find probabilities.
Z-Score FormulaIt is a way to compare the results from a test to a “normal” population.
If X is a random variable from a normal distribution with mean (μ) and standard deviation (σ), its Z-score may be calculated by subtracting mean from X and dividing the whole by standard deviation.
Where, x = test value
μ is mean and
σ is SD (Standard Deviation)
For the averag...