If the P value given in the graph is greater than 5% (0.05) then your data is normally distributed. Your criteria for accepting normality is 5% (0.05). Under ‘options’ menu let the confidence interval be ‘95%’. Select your sample data set which you want to test for normality. Now change the confidence interval to ‘85%’ and recompute the confidence interval on the mean.ĭid the length of the confidence interval change? In a single line comment on ‘why’ it has increased or decreased. Let the confidence interval be ‘95%’ and then calculate the confidence interval on the mean.
In a single line comment why a T test or a Z test is more appropriate here and why? (If a Z test is more appropriate, then use a 1 Sample Z test and if a T test is more appropriate, then use of 1 sample T test).Ĭlick on ‘Options’. Stat>Basic Statistics> 1 sample T test/1 sample Z test Remember cumulative probabilities are always left tailed.Įnter the values of Q1, Q2 and Q3 sequentially under ‘X value’ to find the cumulative probabilities associated with Q1, Q2 and Q3. Under ‘Options’ select ‘Specified X value’ and ‘left tail’. Enter the same sample mean and standard deviation as you used in 1a. Let the distribution be ‘normal’ because we have a normally distributed sample data set.
P (X Probability Distribution Plot>View probability Let the form of input be a ‘single value’. This will give you the three quartiles you need for this question.Ĭalculate >Probability Distribution > Cumulative Probability Distribution (CDF) Remember to enter the same mean and standard deviation as you used in 1a. Stat> Basic Statistics> Display descriptive StatisticsĬlick on ‘Statistics’ and untick all boxes except First Quartile, Median and Third Quartile. In order to do this, you will first need the values for Q1, Q2 and Q3 from your normally distributed sample data set. None of you will have the same normal distribution. This will let each of you create data sets sampled from different normal distributions. Select ‘Normal’ because we want our sample data to be normally distributed.Įnter the value of the Mean and Standard Deviation from Minitab Assignment 1. Later rename that column as ‘Sample Data’. Minitab won’t pick up the column automatically, so you’ll have to manually type in ‘c1’ under ‘Store in Column(s)’.