When you only want to test wether the different treatment had a significant effect, you could run a one-way ANOVA with the treatments as independent variables and the 'origin pro' is the dependent variable (??). When in addition you want to test if time is important you could have several measures over time and test if there are differences between times and whether these differences interact with treatments. A two-way ANOVA would then be appropriate.

Hello Ali Ghaffari. I respectfully take issue with several things you wrote in your Oct 27 post, and I fear that if no one comments, they will mislead and confuse readers who are not well-versed in statistical terminology.

You wrote:

• One-way ANOVA: one group and one dependent variable

If there is only one group, there can be no between-groups variance estimate. Therefore, I wonder if you meant to say one categorical explanatory variable with 2 or more levels and one (quantitative) dependent variable.

You wrote:

• Repeated measure ANOVA: one group and measuring one dependent variable at multiple times
• (Note: In fact, repeated measures ANOVA is the equivalent of the one-way ANOVA.)

I have no major complaint about your description of RM ANOVA, but you could clarify that this is describing a one-factor RM ANOVA model. Why? Because some people use the term RM ANOVA to describe any ANOVA model that includes at least one RM factor.

But I do have some concern about the second statement above, in particular your use of the word equivalent. Perhaps you meant to say that one-factor RM ANOVA is analogous to one-way (between-subjects) ANOVA?

You wrote:

• Two-way ANOVA: three or more groups and one dependent variable

This makes no sense. Two-way (between-Ss) ANOVA is an ANOVA model with exactly two categorical explanatory variables. They are often called A and B generically. And A and B both have at least 2 levels.

You wrote:

• One-way MANOVA: one group and several dependent variables
• Two-way MANOVA: three or more groups and several dependent variables

The same problems I addressed above are repeated here. One-way MANOVA has one categorical explanatory variable with 2 or more levels, not one group. And Two-way MANOVA has exactly 2 categorical explanatory variables, not 3 or more groups.

I hope this helps.

Hi Bruce

You are right about my comment. My comment was oversimplified, and I deleted it to avoid misleading anyone.

Thank you for your comments. I hope that Nishanthini, based on your comments and those of other friends, will be able to choose the appropriate statistical method for his research.

One-Way ANOVA

1. Go to Statistics > ANOVA > One-Way ANOVA.

2. Select columns for dependent and independent variables.

3. Set parameters (e.g., confidence level), then click OK.

Two-Way ANOVA

1. Go to Statistics > ANOVA > Two-Way ANOVA.

2. Choose columns for two independent variables.

3. Adjust settings, then click OK.

Plotting and Labeling

1. Select data and go to Plot to choose a chart type.

2. Right-click on the plot to Add Data Labels and customize as needed.

3. Use Legend or Indexing Options to index the data on the graph.

Zahra Ahmadirad, you have not said which statistical software those instructions apply to.