12.1 What is measured by the estimated standard error that is used for the independent measures t statistic? (Note: For problems 12.2 - 12.3 below, be sure and show a full diagram of the research design as shown in the Formula Sheet and chart attached to this assignment packet. Without using Excel or Chegg, show all steps and calculations you made for each test following the process outlined in the t-test formula sheet handout. What statistical decision do you make in each case? Finally report your results professionally in APA format as found in last step of the formula sheet attached to this assignment packet). 12.2 One sample has n = 14 with SS = 1500, and a second sample has n = 14 with $5 = 1600. a Find the pooled variance for the two samples. Compute the estimated standard error for the sample mean differences (i.e. for the two groups). If the sample mean difference (i.e. M, - M2) is 8 points, is this enough to indicate a significant difference for a two-tailed test at a = .05 level? If the sample mean difference (i.e. M1 - M2) is 12 points, is this enough to indicate a significant difference for a two-tailed test at a = .05 level? 12:3 An educational psychologist would like to determine whether access to computers has an effect on grades for high school students. One group of n = 16 students has home room each day in a computer classroom in which each student is assigned a computer. A comparison group n = 16 has home room in a traditional classroom without computers."At the end of the school year, the average grade is recorded for each student. The data are as follows: Computer Home Room' Traditional Classroom M= 86' M = 82.5 SS = 1005 SS = 1155 Is there a significant difference between the two groups? Use a two- tailed test with a =.05