Question

1. Your little brother just brought home his report card and his teacher indicated that he is struggling with his spelling. Your family looks into programs that will help him improve his spelling and request information from two different spelling programs. One program, SPELLbound, sends you information regarding the effectiveness of their program. You also receive information regarding the effectiveness of a new program on the market, Spelling Foundations. Both programs conducted stats on the pre-program and post-program performance, in the form of a t-test examining the number of errors made in 30 critical words contained in a passage. They have also provided the p values from their respective tests. The information you obtained is listed below.

SPELLbound                                     Spelling Foundations

n = 5000                                              n = 30

SD = 10                                               SD = 10

effect size = 0.10                                effect size = 0.80

p = .004                                               p = .031

a. If your little brother made 15 errors (out of the 30 critical words) at pre-test, what would his number of errors be (out of 30 critical words) after the implementation of each program, assuming his improvements were typical or average (show your calculations)? (4 marks)

2. Which program would you select for your little brother (assume the programs cost the same amount)? Explain your reasoning. (2 marks)

Answer 1

Sola Given & SPELLbound M=5000 Spelling foundations n = 30 SD= 10 effect size=0.80 P=0.031 SD=10 effect Size=0:10 p=0.004 (a) Effect size =poe test enross - post test errors Effect Size = (poe poogoamenroos - post poogdam enrgs) Std. deviation In Spell bound pooqram, effect size =0:10 Hence, 15- post poogsam eros. =0.10 10 - 15-post poogram eodors = 1 post poogoam edsoos = 15-1 14 -0. In spelling foundation Poegsam, effect size Hence, 15-post poogoam erroos = 0.80

15- Post poogsam errors = 8 y post poogsam eroors = 15-8 Above Calculations are done with assumptions that improvements were average. (b) las Both poogsans have shown signiti cant - improvement of student but in and program that es Spelling foundations, the effect size is more implying that spelling mistakes in this program reduced to the extent of 7 in 30 as Composed to iu in 30 of spell bound foundations. Sample size only tends to initiate ourt Statistic and should be considered with caution, we go by eeze which does not depend on sample size and hence decide that spell foundations is more effective program.