Statistics calculators

Test statistic calculator

# Test name
1
One Sample Z-TestCheck that the expected mean is correct, based on a sample average, when you know the standard deviation.
2
One Sample T-TestCheck that the expected mean is correct based on the sample average when you don't know the standard deviation
3
Two Sample Z-TestCompare the average of two groups, when you know the standard deviation.
4
Two Sample T-Test (Pooled variance)Compare the average of two groups, when you don't know the standard deviation, and expect the standard deviation of both groups to be equal.
5
Two Sample T-Test (Welch's)Compare the average of two groups, when you don't know the standard deviation, and expect the standard deviation of both groups to be unequal.
6
Two Sample Mann-Whitney U TestCompare the average of two groups, when you don't know the standard deviation, and expect the standard deviation of both groups to be unequal.
7
Paired T-TestCompare the average of two groups, when you don't know the standard deviation, and expect the standard deviation of both groups to be unequal.
8
Paired Wilcoxon Sign Rank TestCompare the average of two groups, when you don't know the standard deviation, and expect the standard deviation of both groups to be unequal.
9
One Way ANOVA TestCheck if the difference between the average (mean) of two or more groups (populations) is significant, using sample data. ANOVA is usually used when there are at least three groups, since for two groups you can use t tests.
10Chi-Squared Test For Variance
11F Test For Variances
12
Chi-Squared Test For Goodness Of FitCheck if the statistical model fits the observations
13
Shapiro-Wilk TestCheck if the normal distribution model fits the observations
Test Assumptions Required sample data
# Test name Check Statistic
Normal DistributionThe population's distribution is Normal
IndIndependent observations
σYou know the population's standard deviation
σ12The standard deviations of both groups are equal
dYou know the expected difference between the means
μYou know the expected mean
xSample average
nSample size
sSample standard deviation
datarequired full data sample
1
One Sample Z-TestCheck that the expected mean is correct, based on a sample average, when you know the standard deviation.
MeanZ statistic
2
One Sample T-TestCheck that the expected mean is correct based on the sample average when you don't know the standard deviation
MeanT statistic
3
Two Sample Z-TestCompare the average of two groups, when you know the standard deviation.
MeanZ statistic
4
Two Sample T-Test (Pooled variance)Compare the average of two groups, when you don't know the standard deviation, and expect the standard deviation of both groups to be equal.
MeanT statistic
5
Two Sample T-Test (Welch's)Compare the average of two groups, when you don't know the standard deviation, and expect the standard deviation of both groups to be unequal.
MeanT statistic
6
Two Sample Mann-Whitney U TestCompare the median of two groups, when you can't assume normality distribution, the test is robust to outliers.
MedianU statistic
7
Paired T-TestDetermine how a change has taken effect by considering each individual pair as an observation. The test uses T distribution
MeanT statistic Paired
8
Paired Wilcoxon Sign Rank TestDetermine how a change has taken effect by considering each individual pair as an observation. The test uses a ranking methodn
MeanT statistic Paired
9
One Way ANOVA TestCheck if the difference between the average (mean) of two or more groups (populations) is significant, using sample data. ANOVA is usually used when there are at least three groups, since for two groups you can use t-tests.
MeanF statistic
10Chi-Squared Test For Varianceσchi-squared statistic
11F Test For Variances σF statistic
12
Chi-Squared Test For Goodness Of FitCheck if the statistical model fits the observations
Fitchi squared statistic
13
Shapiro-Wilk TestCheck if the normal distribution model fits the observations
Fitw statistic
** - yes, - no, empty - irrelevant

Regression calculators

# Measurement Chart
1Simple Linear RegressionRegression F statistic
2Multiple Linear RegressionRegression F statistic

Sample size calculators

# Distribution Chart
1Chi-Squared sample sizeChi squared Distribution

Distribution calculators

# Distribution Chart
1Normal DistributionNormal Distribution
2T Distribution (Student's)T Distribution
3Chi-Squared DistributionChi squared Distribution
4F Distribution (Fisher-Snedecor)F Distribution

Measurements calculators

# Measurement Chart
1Mean Median Modemean
2Standard DeviationStandard deviation

Guide

Statistical Tests