t-Distribution Table
A t-Distribution Table is a probability distribution table that includes critical values of the t-distribution calculated using a cumulative distribution function.
- Context:
- It can be used for one-tailed and two-tailed tests by using the appropriate value of significance level or upper and lower limits of the region of acceptance.
- It can be referenced by a t-Distribution Calculating System.
- Example(s):
- Table A.2 in http://home.ubalt.edu/ntsbarsh/Business-stat/StatistialTables.pdf
- Table 2 and 3 in http://www.stat.ufl.edu/~athienit/Tables/tables
- Counter-Example(s):
- See: Student's t-Distribution, Statistical Distribution Table.
References
2017
- (Wikipedia, 2016) ⇒ http://en.wikipedia.org/wiki/Student's_t-distribution#Table_of_selected_values
- Most statistical textbooks list t-distribution tables. Nowadays, the better way to a fully precise critical t value or a cumulative probability is the statistical function implemented in spreadsheets, or an interactive calculating web page. The relevant spreadsheet functions are
TDIST
andTINV
, while online calculating pages save troubles like positions of parameters or names of functions.The following table lists a few selected values for t-distributions with ν degrees of freedom for a range of one-sided or two-sided critical regions. For an example of how to read this table, take the fourth row, which begins with 4; that means ν, the number of degrees of freedom, is 4 (and if we are dealing, as above, with n values with a fixed sum, n = 5). Take the fifth entry, in the column headed 95% for one-sided (90% for two-sided). The value of that entry is 2.132. Then the probability that T is less than 2.132 is 95% or Pr(−∞ < T < 2.132) = 0.95; this also means that Pr(−2.132 < T < 2.132) = 0.9. (...)
- Most statistical textbooks list t-distribution tables. Nowadays, the better way to a fully precise critical t value or a cumulative probability is the statistical function implemented in spreadsheets, or an interactive calculating web page. The relevant spreadsheet functions are
2013
- (NIST/SEMATECH, 2013) ⇒ Retrieved on 2017-03-12 from NIST/SEMATECH e-Handbook of Statistical Methods "1.3.6.7.2.-Critical Values of the Student's t Distribution" http://www.itl.nist.gov/div898/handbook/eda/section3/eda3672.htm
- QUOTE: This table contains critical values of the Student's t distribution computed using the cumulative distribution function. The t distribution is symmetric so that
- [math]\displaystyle{ t_{1-\alpha,\nu} = -t_{\alpha,\nu} }[/math]
- The t-table can be used for both one-sided (lower and upper) and two-sided tests using the appropriate value of α.
- The significance level, α, is demonstrated in the graph below, which displays a t distribution with 10 degrees of freedom. The most commonly used significance level is [math]\displaystyle{ \alpha = 0.05 }[/math]. For a two-sided test, we compute [math]\displaystyle{ 1 - \alpha/2 }[/math], or [math]\displaystyle{ 1 - 0.05/2 = 0.975 }[/math] when [math]\displaystyle{ \alpha = 0.05 }[/math]. If the absolute value of the test statistic is greater than the critical value (0.975), then we reject the null hypothesis. Due to the symmetry of the t distribution, we only tabulate the positive critical values in the table below.
2002a
- (Dougherty, 2002) ⇒ Statistical Tables in Dougherty (2002) "Introduction to Econometrics" (second edition 2002, Oxford University Press, Oxford) http://home.ubalt.edu/ntsbarsh/Business-stat/StatistialTables.pdf
2002b
- (Hildebrand,2002) ⇒ http://www.stat.ufl.edu/~athienit/Tables/tables