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`"t-test" = f( 0.05 ,"one-tailed".X,Y)`

Enter a value for all fields

The **paired samples t-test** calculator compares two different sample means from the same sample (Gravetter and Walllnau, 2013). In this case, all subjects participate in all conditions of the test variable.

**INSTRUCTIONS:** Enter the following:

- (
**tails**) One-tail or Two-tail test. - (
**α**) Alpha Value (choose: 0.05, 0.01, 0.005, 0.001) - (
**X,Y**) Enter table of comma separated pairs for Group X and Group Y

**Paired Samples t-test:** The calculator returns the following:

- (
**n)**Number of Pairs - (
**X stats**) The mean (M) and sample standard deviation (SD) of group X. - (
**Y stats**) The mean (M) and sample standard deviation (SD) of group Y. - (
**DF**) The degrees of freedom - (
**CT**) The critical t-value - (
**t**) The t-value - (
**SE**) The Standard Error value.

The computation for a paired samples t-test is similar to that of an independent samples t-test. Similar inputs are used, but it is important to remember they apply to the same sample, not two different samples. To demonstrate this, we will use the dataset "Comfortable TV viewing distance for college students" located HERE. The data presented here can be input to the equation, which will return the means and standard deviations of both test samples (M and SD) and a summary of the results, including degrees of freedom (df), a critical t-value, your t-score, and the standard error (SE).

If you plug in the data values, you should get a return string that looks like this: Sample 1: M = 6, SD = 1.67. Sample 2: M = 5.17, SD = 2.23. Summary: df = 5, critical t-value = 2.015, t-value = -0.62, and SE value is 1.35. This tells us that the difference between the two means is not significant, because our t-value is not beyond the critical t-value. In context, according to this hypothetical data, college students do not find one TV viewing distance (8ft or 12 ft) more comfortable than another; they are roughly equally comfortable.

Gravetter, F. J., & Wallnau, L. B. (2013). *Statistics for the Behavioral Sciences*. Wadsworth, CA: Cengage Learning.

The example provided in the dataset was adapted from the textbook.

**Observational Stats**: This function accepts a table of numbers separated by commas and calculates observational statistics for any of the columns. This includes count, min, max, sum, sum of squares (Σx²), square of the sum (Σx)², mean, median, mode, range, mid point, rand, sort up, sort down, rand, population variance, population standard deviation, the sample/experimental variance, sample/experimental standard deviation.**Frequency Distribution**: This function lets you enter a string of numbers separated by commas, a low and high range and a number of bins. It then computes how many of the observations are in each of the bins between the high and low values designated.**Paired Sample t-test**: This computes the various parameters associated with the Paired Sample t-test.**ANOVA (one way)**: The is one way analysis of variance**(χ**This computes the Chi-Square value for an nxm array of data and provides the degrees of freedom.^{2}) Chi-Square Test:**Linear Regression**: This computes the regression line (least-squares) through a set of X and Y observations. It also computes the regression coefficient (r).**y = a + bx**: This is linear equation used with Linear Regression to predict values of Y.**Wilcoxon Signed Rank Test**: This provides the Wilcoxon statistics and critical value for two groups of numeric observations based on an alpha value and whether it's a one or two tailed test.- Slope-Intercept form of a Line based on two points.
- Slope between two points
- Range value based on the slope-intercept formula of a line and a value of the domain.
- Compute the Probability between z SCORES
- College Level Statistics Calculator (Stat Calc).
- Count of Observations in a Set - this is the number (n) of values in a set.
- Minimum Value in a Set - this is the minimum observed value
- Maximum Value in a Set- this is the maximum value in the set.
- Numeric Sort (up and down) - this returns a comma separated list of the observations in ascending or descending order.
- Create a random subset of the a list of numeric values
- Random number from a range you specify
- Frequency distribution of data.
- Σx - this is the sum of the values in a set.
- Σx² - this is the sum of the squared values
- (Σx)² - this is the square of the summed values.
- Mean
- Median - the middle ordered value
- Mode - the most recurring observation
- Mid Point in a Set - this is the mid point of the observation range.
- Range in a Set - this is the difference between the max and the min.
- Population Variance of the values
- Population standard deviation of the values
- Sample Variance of the values
- Sample Standard Deviation of the values
- Compute the z SCORE based on the mean and standard deviation
- Compute the z SCORE in a set of observations
- Compute the percentile of a single observation (y) in a set (X)
- SDOM - standard deviation of mean
- Percent Relative Standard Deviation