Figure 4.

Monthly vocabulary as a function of pointing status. For reported data (top 2 rows, CDI receptive and productive) we show 9–12mo. as these had the most even distribution of non-pointers and pointers (see Table 3). For observed data, we show 11–14mo., since mean, median, and mode productive vocabulary at 9 and 10mo. was 0. Top label of panel indicates month, bottom label indicates number of non-pointers(np) and pointers(p); e.g. top left: at 9mo. there are 26 non-pointers and 18 pointers reported). Y-axis is log scaled. The third row depicts observed data (i.e. # child-produced (CHI) noun-types). Grey bars (left of each pair of bars) indicate non-pointers, colored bars indicate pointers. Error bars show standard error.