Author(s) This pre-registration is currently anonymous to enable blind peer-review. It has one author.
Pre-registered on 2021/10/28 - 07:27 PM (PT)
1) Have any data been collected for this study already? No, no data have been collected for this study yet.
2) What's the main question being asked or hypothesis being tested in this study? In this experiment, we look at 2- to 4-year-old children's ability to map emotion words to emotional facial expressions. Participants will see two pictures in which two children make different facial emotional expressions and hear some sentences that involve an emotion word (e.g., "Who is happy? Can you show me who is happy?"). The participants will be asked to point at the picture that matches the audio they hear. Four emotion words and their corresponding facial expressions are tested: happy, sad, angry, and scared. We predict that as children get older, they are increasingly able to understand these emotion words and connect them to their corresponding facial expressions.
3) Describe the key dependent variable(s) specifying how they will be measured. Whether a participant points to the target picture (score: 1) or the distractor (score: 0) on each trial
4) How many and which conditions will participants be assigned to? There are 4 emotion category conditions with 6 pictures in each of the emotion categories. In total we will have 24 trials. Each child will receive all 24 trials. On each trial, we will randomly select one picture from one category and another picture from another category, and randomly select an audio clip that matches one of the two pictures, yet we also add the constraint that each picture and each audio clip will be selected evenly across the 24 trials.
5) Specify exactly which analyses you will conduct to examine the main question/hypothesis. (1) We will use a mixed-effects model to analyze our data: glmer (score ~ trial_type * age + (trial_type * emotion | subject)), in which
- score: score (0 or 1) on each trial
- trial_type: within-valence or cross-valence trial (sum coded; -.5 for within-valence and +.5 for cross-valence)
- age: each child's age (centered for interpretability)
- emotion: target emotion on each trial
- subject: subject id.
If the model fails to converge, we will simplify the random effects according to Langcog Lab standard operating procedure (first prune random interaction slopes, then random slopes, then intercepts).
We will interpret the intercept and the corresponding pvalue as evidence regarding whether the overall level of performance is above chance. We will interpret the estimates for trial_type and age and their pvalues as evidence regarding whether these factors have significant effects.
(2) We will run one-sample t-tests to examine if children's performance is above chance. If there is an effect of age and/or trial type, we will split the data first and run these t-tests in each age group and/or trial type.
6) Describe exactly how outliers will be defined and handled, and your precise rule(s) for excluding observations. We will exclude subjects if we observe the following:
- if a child completes less than ⅓ of the trials
- if a child has been diagnosed with disabilities or disorders (e.g., autism)
- if a child has seen another kid complete the study
- if a child is a non-English speaker
- if there are technical issues related to online testing (e.g., slow internet speed),
- if the overall accuracy is 3 standard deviations of the mean.
- We will also exclude data points on particular trials if there is parental or sibling interference. If there is parental or sibling interference on over ⅓ of the trials, we will exclude data from the subject as a whole.
7) How many observations will be collected or what will determine sample size? No need to justify decision, but be precise about exactly how the number will be determined. We will collect N = 48 children (16 2-year-olds, 16 3-year-olds, and 16 4-year-olds).
8) Anything else you would like to pre-register? (e.g., secondary analyses, variables collected for exploratory purposes, unusual analyses planned?) At the end of the study we will be including a survey about children's exposure to other people wearing masks in the past year. We are curious to see if this has any effect on the children's performance on our task.
We will also explore if children perform equally well on each emotion category, and compare data from this experiment with that from another experiment, which uses similar materials but includes congruent body language as cues to emotion.
