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Statistics
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Excel FunctionsTDIST, TINV,FDIST, FINV,CHIDIST,CHIINV, NORMDIST, NORMSINV TDISTReturns the Percentage Points (probability) for the Student tdistribution where a numeric value (x) is a calculated value of t for which the Percentage Points are to be computed. The tdistribution is used in the hypothesis testing of small sample data sets. Use this function in place of a table of critical values for the tdistribution. Syntax TDIST(x,degrees_freedom,tails) X is the numeric value at which to evaluate the distribution. Degrees_freedom is an integer indicating the number of degrees of freedom. Tails specifies the number of distribution tails to return. If tails = 1, TDIST returns the onetailed distribution. If tails = 2, TDIST returns the twotailed distribution. Remarks
Example
TINVReturns the tvalue of the Student's tdistribution as a function of the probability and the degrees of freedom. Syntax TINV(probability,degrees_freedom) Probability is the probability associated with the twotailed Student's tdistribution. Degrees_freedom is the number of degrees of freedom to characterize the distribution. Remarks
TINV uses an iterative technique for calculating the function. Given a probability value, TINV iterates until the result is accurate to within ± 3x10^7. If TINV does not converge after 100 iterations, the function returns the #N/A error value. Example
FDISTReturns the F probability distribution. You can use this function to determine whether two data sets have different degrees of diversity. For example, you can examine test scores given to men and women entering high school and determine if the variability in the females is different from that found in the males. Syntax FDIST(x,degrees_freedom1,degrees_freedom2) X is the value at which to evaluate the function. Degrees_freedom1 is the numerator degrees of freedom. Degrees_freedom2 is the denominator degrees of freedom. Remarks
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Returns the inverse of the F probability distribution. If p = FDIST(x,...), then FINV(p,...) = x. The F distribution can be used in an Ftest that compares the degree of variability in two data sets. For example, you can analyze income distributions in the United States and Canada to determine whether the two countries have a similar degree of diversity. FINVReturns the inverse of the F probability distribution. If p = FDIST(x,...), then FINV(p,...) = x. The F distribution can be used in an Ftest that compares the degree of variability in two data sets. For example, you can analyze income distributions in the United States and Canada to determine whether the two countries have a similar degree of diversity. Syntax FINV(probability,degrees_freedom1,degrees_freedom2) Probability is a probability associated with the F cumulative distribution. Degrees_freedom1 is the numerator degrees of freedom. Degrees_freedom2 is the denominator degrees of freedom. Remarks
FINV can be used to return critical values from the F distribution. For example, the output of an ANOVA calculation often includes data for the F statistic, F probability, and F critical value at the 0.05 significance level. To return the critical value of F, use the significance level as the probability argument to FINV. FINV uses an iterative technique for calculating the function. Given a probability value, FINV iterates until the result is accurate to within ± 3x10^7. If FINV does not converge after 100 iterations, the function returns the #N/A error value. Example
CHIDISTReturns the onetailed probability of the chisquared distribution. The γ2 distribution is associated with a γ2 test. Use the γ2 test to compare observed and expected values. For example, a genetic experiment might hypothesize that the next generation of plants will exhibit a certain set of colors. By comparing the observed results with the expected ones, you can decide whether your original hypothesis is valid. Syntax CHIDIST(x,degrees_freedom) X is the value at which you want to evaluate the distribution. Degrees_freedom is the number of degrees of freedom. CHIINVReturns the inverse of the onetailed probability of the chisquared distribution. If probability = CHIDIST(x,...), then CHIINV(probability,...) = x. Use this function to compare observed results with expected ones to decide whether your original hypothesis is valid. Syntax CHIINV(probability,degrees_freedom) Probability is a probability associated with the chisquared distribution. Degrees_freedom is the number of degrees of freedom. Remarks
CHIINV uses an iterative technique for calculating the function. Given a probability value, CHIINV iterates until the result is accurate to within ± 3x10^7. If CHIINV does not converge after 100 iterations, the function returns the #N/A error value. Example
NORMDISTReturns the normal cumulative distribution for the specified mean and standard deviation. This function has a very wide range of applications in statistics, including hypothesis testing. Syntax NORMDIST(x,mean,standard_dev,cumulative) X is the value for which you want the distribution. Mean is the arithmetic mean of the distribution. Standard_dev is the standard deviation of the distribution. Cumulative is a logical value that determines the form of the function. If cumulative is TRUE, NORMDIST returns the cumulative distribution function; if FALSE, it returns the probability mass function. Remarks
Example
NORMSINVReturns the inverse of the standard normal cumulative distribution. The distribution has a mean of zero and a standard deviation of one. Syntax NORMSINV(probability) Probability is a probability corresponding to the normal distribution. Remarks
NORMSINV uses an iterative technique for calculating the function. Given a probability value, NORMSINV iterates until the result is accurate to within ± 3x10^7. If NORMSINV does not converge after 100 iterations, the function returns the #N/A error value. Example




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Last Modified:
01/06/06 