About Mutua

Mutua · ‎01-05-2016

Thanks Keshan for the reply. I will follow up with the editor for further guidance on the issue. Best regards, Peter

Mutua · ‎01-05-2016

Thanks Reeza for the feedback. I really appreciate. I will follow it up with the editor and see what can be done or if there are issues i missed in the table. Best regards, Peter.

Mutua · ‎01-05-2016

Dear Reeza, What type of additioal analysis should i have performed to get this details on "first level risk"? Regards, Peter.

Mutua · ‎01-05-2016

Dear Reeza, its "the first level of risk" that the editor is asking for.

Mutua · ‎01-05-2016

Thankyou Reeza for the reply. To explain i had a treatment where i added a biological control and the pathogen in the soil where potato plant was planted. The other treatment was where i added the pathogen alone and also a potato plant was included (all in pots). Each treatment was replicated 10 times. At the end of the experiment i extracted the pathogen and determined the population. The main intention was to detect if the biological control agent had any influence on the pathogen. I then performed a Ttest to compare the means between those treatments with pathogens and those without. The results indicated that adding the biocontrol led to higher pathogen numbers and therefore significantly different from that without the biological control. The reviewer states that i should state the level of risks associated with the signficant differences between the means (if i get it right). Its my hope that the question is abit clearer. Looking forward to your feedback. Best regards, Peter

Mutua · ‎01-05-2016

Dear ballardw, Yes i have read, but i have not come across that term before. Please kindy explain. Best regards, Peter

Mutua · ‎01-05-2016

Dear SAS community, I have a simple question that came from a reviewer of my mnuscript, but i can´t get my head around it. I performed a t-test where i compared two means. I found that there are signficant differences between the means. Therefore i created a table of each comparison and indicated the signficance difference using asterisks. However the editor of the journal has constantly asked me to state the first level risk associated wth the results i gave in the table of the t-test comparisons. My questions is what is the reviewer asking for? that i state its type one error and the risk levels are less than 0.05? (p-value limit)? Your support is highly appreciated. Best regards, Peter.

Mutua · ‎11-20-2015

Many thanks for that informative email. I really appreciate. I am getting the same kind on information when i run my analysis. Going by your example, it means that F(DF1, DF2) = F(8, 9) =1.03 right? What does it mean when the DF1 and DF2 are the same? and when the P-value is small enough to enable rejection of the null hypothesis? Best regards, Peter

Mutua · ‎11-20-2015

Dear Slchen, Thanks too for the feedback. What then does it mean when i have similar DF for both Numerator and denominator? Here are the details of my results pooled DF=14 Satterthwaite (unequal) DF = 11.96 Folded F: Num DF = 7, Den DF=7, F value = 2.41. So in this case, is my F(DF1, DF2) = F(7,7)= 2.41? If yes, what does this mean? Best regards, Peter.

Mutua · ‎11-20-2015

Dear Rick, Many thanks for the feedback. The reviewer of the manuscript states that i should report all F-values with their two df each. No other information is given. My assumption is they want to check the credibility of the statisitics provided. Being a basic user of SAS, i am not sure how to program my SAS Procedure to obtain this information. I apprecite your feedback. Am able to get the information you stated i.e. Satterthwaite (unequal varince) and equal varince test results. Also the folded F test results. I have looked at the link you gave Is there a standard Procedure in SAS to do this automatically in SAS? Best regards, Peter.

Mutua · ‎11-20-2015

Dear Community, I recently recently performed a Ttest on my data following the Proc below: Proc Ttest; Class Trt; Var PFG Male Female; Run; I am able to get only one F value, yet the reviewer of my manuscript would like me to report me the F-values with their two DF each. Am not sure how to go about this procedure. I will really appreciate your help if you can guide me on the procedure to follow. Best regards, Peter

Mutua · ‎12-04-2014

Thanks Steve for your suggestions and answer to my question. I agree with the argument since the subject were destroyed and not replaced during the analysis. True, choosing the right model was difficult, because i choose Proc Mixed. But with the additional information, and the preference for GLIMMIX, then, i will work around and find how to carry out the analysis. Could i have more questions, i will post them out again to the SAS community. I thank you so much for your continued support in my quest to learn more Statistical procedure. Thumbs up. Peter

Mutua · ‎12-01-2014

Dear SAS community, I did an experiment in climate chambers (different temperatures) with plants infested with two different fungal species. To investigate the development and severity of disease, i sampled 15 plants from each treatment (per climate chamber/ temperature). The plants were used for destructive analysis i.e they were not replaced. The sampling was done per month for a total of four months. The objective of the study was to investigate the influence of temperature on disease severity and growth of the plants. Statistical question: 1. Should i perform a repeated measurement analysis on these data? 2. If Yes to question 1, is Proc mixed model the best statistical procedure for this type of analysis? Your support will be highly appreciated. Regards, Peter.

Mutua · ‎10-20-2014

Thanks Steve for your informative answer. I will run the analysis and if i have further question i will post it to the SAS support communities again. Best regards, Peter

Mutua · ‎10-20-2014

Dear SAS community, I performed two repeated experiments with potted plants in two climate chambers set at different day and night temperatures (20°C day and 12°C night temp for climate chamber 1) and (26°C day temp and 19°C temp for night temp in chamber two). There were three treatments in each chamber which included one level of fungi infestation, one level of bacteria infestation and control plants (not infested), each replicated 20 times. To assess the levels of damage on each plants, 5 plants from each treatment (making a total of 15 plants per climate chamber were harvest per week. Also above fresh plant weight was measured per pot. The objective of the experiment was to evaluate the influence of temperature on disease severity and development on plants in two climate chambers. Statistical questions: 1: should i treat the two climate chambers as pseudoreplicates? (i.e n=2)? 2. If yes to question 1, what is the best SAS procedure to handle this type of data? Proc GLIMMX? Your support with this issue will be truly appreciated. Best regards, Peter

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Re: Finding levels of risks associated with t-test

Re: Finding first level risk associated with t-test

Re: Finding first level risk associated with t-test

Re: Finding levels of risks associated with t-test

Re: Finding levels of risks associated with t-test

Re: Finding levels of risks associated with t-test

Finding levels of risks associated with t-test

Re: How to obtain the two DF in Proc Ttest e.g. F(df1, df2) = XXX

Re: How to obtain the two DF in Proc Ttest e.g. F(df1, df2) = XXX

Re: How to obtain the two DF in Proc Ttest e.g. F(df1, df2) = XXX

Re: How to obtain the two DF in Proc Ttest e.g. F(df1, df2) = XXX

Re: Finding levels of risks associated with t-test

Re: Finding first level risk associated with t-test

Re: Finding first level risk associated with t-test

Re: Finding levels of risks associated with t-test

Re: Finding levels of risks associated with t-test

Re: Finding levels of risks associated with t-test

Finding levels of risks associated with t-test

Re: How to obtain the two DF in Proc Ttest e.g. F(df1, df2) = XXX

Re: How to obtain the two DF in Proc Ttest e.g. F(df1, df2) = XXX

Re: How to obtain the two DF in Proc Ttest e.g. F(df1, df2) = XXX

How to obtain the two DF in Proc Ttest e.g. F(df1, df2) = XXX

Re: Repeated measurements analysis....Which is the best SAS procedure?

Repeated measurements analysis....Which is the best SAS procedure?

Re: Analysis of data with pseudoreplicates

Analysis of data with pseudoreplicates