Hello!
I am working in my Master Thesis and I have some questions regarding the design of my experiment and the analysis of the data, could you please help me?
I am looking at the effect of Temperature, Ionic strength and pH in the solubility. For this, I followed the following steps:
1) I first look into the independent effect of each variable:
a) Temperatures (20, 70, 80 and 90) vs solubility
b) pH (3, 4, 5, 6, 7, 8) vs solubility
c) Ionic strength (0.5%, 1%, 1.5%, 2%)
My objective by doing this was to analyze the relation between each independent variable and the dependent variable. For temperature and ionic strength , I obtained a linear relation, but in the case of pH I obtained a curve (Uform).
2) Now, I would like to perform a 2 level factorial experiment (2^3) to look at the combined effect of the independent variables. I will choose the minimum and maximums for each variable based on the results of the previous experiments. By doing this, I would have 8 experiments to perform.
3) Now, I would like to obtain the coefficients of each independent variable and of their combination. Should I use MANOVA or multiple regression?
I was reading that in the case of multiple regression I need at least 30 samples to have significant results. What does it mean? That I have to repeat 4 times the 2 level factorial experiment? or that 2 levels (min and max) are not enough for conducting a multiple regression?
I will really appreciate any suggestion or guidance,
Thanks in advance,
Joss
I am working in my Master Thesis and I have some questions regarding the design of my experiment and the analysis of the data, could you please help me?
I am looking at the effect of Temperature, Ionic strength and pH in the solubility. For this, I followed the following steps:
1) I first look into the independent effect of each variable:
a) Temperatures (20, 70, 80 and 90) vs solubility
b) pH (3, 4, 5, 6, 7, 8) vs solubility
c) Ionic strength (0.5%, 1%, 1.5%, 2%)
My objective by doing this was to analyze the relation between each independent variable and the dependent variable. For temperature and ionic strength , I obtained a linear relation, but in the case of pH I obtained a curve (Uform).
2) Now, I would like to perform a 2 level factorial experiment (2^3) to look at the combined effect of the independent variables. I will choose the minimum and maximums for each variable based on the results of the previous experiments. By doing this, I would have 8 experiments to perform.
3) Now, I would like to obtain the coefficients of each independent variable and of their combination. Should I use MANOVA or multiple regression?
I was reading that in the case of multiple regression I need at least 30 samples to have significant results. What does it mean? That I have to repeat 4 times the 2 level factorial experiment? or that 2 levels (min and max) are not enough for conducting a multiple regression?
I will really appreciate any suggestion or guidance,
Thanks in advance,
Joss
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