Domenica DiStasio Exercise 3 Main Effects and Interactions non statistical 1 First grade students rate a substitute teacher in terms of likability on a 10 point scale where 1 is did not like at all and 10 is liked very much The teacher is either a male of female and is dressed in either a suit or in jeans and a tee shirt Dress of Teacher Suit Jeans Sex of Male 5 9 Teacher Female 7 7 9 9 8 10 a Is there a main effect of Dress of Teacher YES If YES then describe the effect by referring to the marginal means Teachers dressed in jeans t shirt are rated more likeable M 8 than those who dress in suits M 6 b Is there a main effect of Sex of Teacher NO If YES then describe the effect by referring to the marginal means c Generate an interaction graph for these data and paste it below Domenica DiStasio Exercise 3 Chart Title 10 9 8 7 6 5 4 3 2 1 0 1 2 d Is there an interaction of Dress and Sex of Teacher YES If YES then describe the interaction by talking about the graph The mean difference between male teachers wearing jeans tshirt was higher 4 than it was in females 0 because females had no mean difference Domenica DiStasio Exercise 3 2 The data below are from a study of the effects of a new drug Remoh on memory for different types of elderly residents at a nursing home The data are represented as the mean number of words recalled out of 20 Drug Condition Resident Type Placebo Remoh Alzheimer s 9 16 Non Alzheimer s 12 19 12 5 15 5 10 5 17 5 a Is there a main effect of Drug Condition YES If YES then describe the effect by referring to the marginal means The effects of the placebo M 10 5 on memory for the elderly was lower than the effects of the Remoh drug M 17 5 b Is there a main effect of Resident Type YES If YES then describe the effect by referring to the marginal means Mean of non Alzheimer s patient recall higher M 15 5 than Alzheimer s patients M 12 5 c Generate an interaction graph for these data and paste it below Chart Title 20 15 10 5 0 1 2 Domenica DiStasio d Is there an interaction of Drug Condition and Resident Type YES NO If YES then describe the interaction by talking about the graph No interaction for both patients the drug was better than the placebo Exercise 3 Domenica DiStasio Exercise 3 3 Thirty 16 year old women and thirty 40 year old women were brought in to a sleep lab here at UMass Half of each group was allowed to sleep uninterrupted for 8 hours no deprivation The other halves of each group were allowed to sleep for 8 hours but were woken up each time they entered REM sleep REM deprivation All participants then engaged in a task involving memorizing strings of random numbers Performance was recorded as percentage of numbers recalled Sleep Deprivation Age Group None REM deprived 16 years 75 25 40 years 55 45 65 35 a Is there a main effect of Sleep Deprivation YES If YES then describe the effect by referring to the marginal means The lines in the graph are not parallel meaning that there is in interaction in age group and sleep deprivation they started higher and ended up lower Sleep deprived subjects had lower recall percentage M 35 than the not sleep deprived M 65 b Is there a main effect of Age Group NO If YES then describe the effect by referring to the marginal means c Generate an interaction graph for these data and paste it below Domenica DiStasio Exercise 3 Chart Title 80 70 60 50 40 30 20 10 0 1 2 d Is there an interaction of Sleep Deprivation and Age Group YES If YES then describe the interaction by talking about the graph Non sleep deprived 16 year olds were able to recall higher percentage 50 than non sleep deprived 40 year olds 50 while sleep deprived 40 year olds recalled higher than sleep deprived 16 year olds Domenica DiStasio Exercise 3 4 The following data are from a study of the effects that distraction and difficulty level have on reading comprehension The data are presented as the mean number of correct responses on a comprehension test Distraction TV off TV on Difficulty Easy 20 18 level Hard 15 8 a Is there a main effect of Distraction YES NO If YES then describe the effect by referring to the marginal means People who have the TV on M 13 got less correct on the reading comprehension than those with TV off 17 5 b Is there a main effect of Difficulty level YES NO If YES then describe the effect by referring to the marginal means There are lower scores for the hard level reading comprehension test meaning that the tv was interacting with the scores that people were getting on the exam c Generate an interaction graph for these data and paste it below Domenica DiStasio Exercise 3 Chart Title 25 20 15 10 5 0 1 2 d Is there an interaction of Distraction and Difficulty YES If YES then describe the interaction by talking about the graph The lines of the graph would eventually interact The TV being off would eventually interact with the TV being on so as the distraction increases the difficulty level also increases The mean difference between TV on and TV OFF is 2 with the easy level than the harder comprehension test had a higher difference of the groups with TV on and the groups of TV off which is 7 Domenica DiStasio Exercise 3 5 An experimenter is interested in the effects of musical training and various types of music on memory during study She was able to recruit subjects with more than five years of musical training and some with no formal training at all She decided to look at three study conditions silence music without lyrics and music with lyrics and all subjects were randomly assigned one of the three conditions All participants saw the same list of words The data were recorded as the percentage of words recalled from the list during the test phase of the experiment Musical Training Minimal Five years Silence 78 85 Type of Music No Lyrics 73 60 Lyrics 60 55 a Is there a main effect of Musical Training YES NO If YES then describe the effect by referring to the marginal means People with minimal training had a higher percentage of words recalled from the list M 70 3 during the test phase than those with five years of experience M 66 7 b Is there a main effect of Type of Music YES NO If YES then describe the effect by referring to the marginal means There are lower scores for the music with lyrics M 57 5 in comparison to no lyrics M 66 6 and silence …