Tham khảo tài liệu 'product and process comparisons_10', kỹ thuật - công nghệ, điện - điện tử phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | . 1-Way ANOVA calculations ENGINEERING STATISTICS HANDBOOK hW tools raids lỉEÂtCH BACK Nixf 7. Product and Process Comparisons . Comparisons based on data from more than two processes . Are the means equal ANOVA calculations Formulas Although computer programs that do ANOVA calculations now are for 1-way common for reference purposes this page describes how to calculate the ANOVA various entries in an ANOVA table. Remember the goal is to produce hand two variances of treatments and error and their ratio. The various calculations computational formulas will be shown and applied to the data from the previous example. Step 1 compute CM STEP 1 Compute CM the correction for the mean. Step 2 compute total SS STEP 2 Compute the total SS. The total SS sum of squares of all observations - CM -yỵỵ -cM Í-1 j-1 2 2 - 2 http div898 handbook prc section4 1 of 2 5 1 2006 10 38 56 AM . 1-Way ANOVA calculations The SS is called the raw or uncorrected sum of squares. Step 3 compute SST STEP 3 Compute SST the treatment sum of squares. First we compute the total sum for each treatment. T1 . T2 . T1 . Then 3 Y S SST y i--CM Ù Kị .Ế Ê ííỉí- w 5 5 5 Step 4 compute SSE STEP 4 Compute SSE the error sum of squares. Here we utilize the property that the treatment sum of squares plus the error sum of squares equals the total sum of squares. Hence SSE SS Total - SST - . Step 5 Compute msT mse and F STEP 5 Compute MST MSE and their ratio F. MST is the mean square of treatments MSE is the mean square of error MSE is also frequently denoted by đ . MST SST k-1 2 MSE SSE N-k 12 where N is the total number of observations and k is the number of treatments. Finally compute F as F MST MSE That is it. These numbers are the quantities that are assembled in the ANOVA table that was .
