ANOVA Two-Factor without Replication is used for a design of two factors (e.g., Factor A and Factor B) and only 1 observation in each cell. For instance, both Factor A and Factor B have two levels, leading to 4 cells in total. Each cell only has 1 observations (see below). Variance Partitioning Two-Factor ANOVA without … Read more
You use ANOVA: Two-Factor without Replication when each cell only has 1 observation, but use Two-Factor with Replication when each cell has more than 1 observation. For instance, there are two factors, City and Chain Brand. Each has 2 levels, leading to 4 cells (see the figure below). Each cell in the left-hand data table … Read more
This tutorial explains the difference between logit and probit in statistics with formulas and examples. Formula and Example for Logit We can start with the following formula. Thus, \( \beta_0+\beta_1x_1+…+\beta_nx_n \) can be from \( -\infty \) to \(+\infty \), and \( p(y=1) \) will be always within the range of \( (0,1) \). We … Read more
This tutorial will first show the formulas for Two-way ANOVA and then use an example to show how you can calculate two-way ANOVA by hand. The following depicts the conceptual framework of the variance breaking down for two-way ANOVA. Typically, Two-way is used for experiment data analyses. Data example for two-way ANOVA This is the … Read more
This tutorial includes the formula and examples for Sum of Squares (SS). Sum of Squares (SS) is a measure of deviation from the mean and the following is its formula. It is to square the distance between each data point and the mean then add them together. Formula of Sum of Squares (SS) The following is … Read more
The main difference between interval and ratio data lies in the presence or absence of a meaningful zero point and the nature of the numerical values. Interval Data Interval data is a type of quantitative data where the intervals between values are equal and consistent. It has a numerical scale that represents the magnitude of … Read more
Likert scales are widely used in surveys and questionnaires to assess respondents’ attitudes, opinions, or perceptions. However, there has been ongoing debate regarding whether Likert scales should be classified as ordinal data or interval data. This tutorial aims to explore the nature of Likert scales and provide insights into their appropriate treatment in statistical analysis. … Read more
There are 3 assumption for ANOVA: Normality – The responses for each factor level have a normal population distribution. Equal variances (Homogeneity of Variance) – These distributions have the same variance. Independence – The data are independent. You can use R to test the assumptions of normality and equality variances (The following are the two tutorials). In contrast, … Read more
In some situations, the syntax is easier than the visual menu to use in SPSS. This tutorial provides examples of syntax for chi-square test in SPSS. 2 Examples of Syntax for chi-square test in SPSS Example 1: One variable The first example is the one variable chi-square test. The following is example data for one … Read more
This tutorial shows how you can do one variable chi-square in SPSS with detailed examples. The following shows two examples, one using Syntax and one using a menu interface. Examples of One Variable Chi-Square in SPSS Example 1 A school is offering 3 courses, and you would like to see whether the number of students … Read more