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I am new user of R software. I have 2 types of experiments.

  1. I want to analyze data from 10 jujube varieties and harvested fruits at 4 maturity stages. The effect of varieties is fixed while that of harvesting stages is random.
  2. I harvested fruits of two varieties and applied 4 different treatments to these fruits and analyzed on weekly basis up to 35 days. I want to use repeated measures ANOVA. Kindly help me some workable commands and helpful R packages. An response will be highly appreciated. Thanking in advance

Regards Zafar Iqbal

dataset for first case (head(data, 10) sub varieties stages width 1 1 Anokhi S1 27.08 2 1 Anokhi S1 27.15 3 1 Anokhi S1 26.87 4 1 Desikarela S1 26.21 5 1 Desikarela S1 23.47 6 1 Desikarela S1 23.77 7 1 Dilbahar S1 30.38 8 1 Dilbahar S1 26.80 9 1 Dilbahar S1 29.69 10 1 Gurh S1 20.57)

(str(data, 10) 'data.frame': 120 obs. of 4 variables: $ sub : int 1 1 1 1 1 1 1 1 1 1 ... $ varieties: chr "Anokhi" "Anokhi" "Anokhi" "Desikarela" ... $ stages : chr "S1" "S1" "S1" "S1" ... $ width : num 27.1 27.1 26.9 26.2 23.5 ...)

dataset for second case

(head(data, 10) sub var trt stor TSS 1 1 Umran NoHWT 0day 10.00 2 1 Umran NoHWT 0day 9.70 3 1 Umran NoHWT 0day 9.80 4 1 Umran HWT1 0day 10.20 5 1 Umran HWT1 0day 9.75 6 1 Umran HWT1 0day 9.86 7 1 Umran HWT2 0day 9.65 8 1 Umran HWT2 0day 9.72 9 1 Umran HWT2 0day 9.81 10 1 Umran HWT3 0day 9.45)

(str(data, 10) 'data.frame': 144 obs. of 5 variables: $ sub : int 1 1 1 1 1 1 1 1 1 1 ... $ var : chr "Umran" "Umran" "Umran" "Umran" ... $ trt : chr "NoHWT" "NoHWT" "NoHWT" "HWT1" ... $ stor: chr "0day" "0day" "0day" "0day" ... $ TSS : num 10 9.7 9.8 10.2 9.75 9.86 9.65 9.72 9.81 9.45 ...)

I am using following commands in R software for Repeated measures ANOVA. Whether these are workable or suggest me best alternates.

                                                                   (```>library(car)

options(contrasts = c("contr.sum", "contr.poly"))

model<-lm(vitc~varieties+stages+varieties:stages, data=data)

Anova(model, type="III")

library(agricolae)

(HSD.test(model, "varieties")$groups)

(HSD.test(model, "stages")$groups)```)

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  • $\begingroup$ What is your research question ? Also, please desribe the dataset. Please list all the variables and explain what they are, and what kind of values they may take. $\endgroup$ – Robert Long Jan 28 at 17:08
  • $\begingroup$ 1. To study the effect of jujube varieties and level of harvest maturity on physical, chemical and phytochemical attributes of fruit. The datasets are comprised of 120 obsevations 10 varieties * 4 stages * 3 replicates for each quality parameter. $\endgroup$ – Zafar Iqbal Feb 1 at 16:04
  • $\begingroup$ 2. in second situation, jujube fruits from 2 varieties were harvested and treated with 3 hot water dippings at different time temperature combinations and 4th one serve as control. fruits after treatments were stored at 5C and analyzed on day 0 as well after one week interval for different quality parameters up to 35 days. The objective is to investigate the effect of varieties, treatments and storage interval on quality attributes of jujube fruits. $\endgroup$ – Zafar Iqbal Feb 1 at 16:51
  • $\begingroup$ Kindly suggest me workable commands and useful R packages to solve these as repeated measures ANOVA and Tukey's HSD test for multiple mean comparison. $\endgroup$ – Zafar Iqbal Feb 1 at 16:51
  • $\begingroup$ Parameters are fruit length, frimness, TSS, Acidity, Vit C Etc. These are physical, chemical and phytochemical parameters and may take continuous values. $\endgroup$ – Zafar Iqbal Feb 1 at 16:59

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