Two methods for quantifying similarity between textbooks with respect to content distribution

Figures & data

Table 1. The eight categories of FoNS.

	In relation to the integers 0–20, children are encouraged to …
FoNS1	Identify, name and write particular number symbols
FoNS2	Count systematically, forwards and backwards, from arbitrary starting points
FoNS3	Understand the one-to-one correspondence between number and quantity
FoNS4	Compare magnitudes and deploy language like ‘bigger than’ or ‘smaller than’
FoNS5	Recognize and make connections between different representations of number
FoNS6	Estimate, whether it be the size of a set or an object
FoNS7	Undertake simple addition and subtraction tasks
FoNS8	Recognize and extend number patterns, identify a missing number

Table 2. Counts and proportions of FoNS in three textbooks.

Textbook	Abacus		Singma		MNP
Total units of analysis	1 522		1 693		1 955
FoNS1	738	48%	614	36%	690	35%
FoNS2	250	16%	214	13%	269	14%
FoNS3	339	22%	335	20%	371	19%
FoNS4	57	4%	110	6%	120	6%
FoNS5	275	18%	346	20%	370	19%
FoNS6	6	0%	0	0%	0	0%
FoNS7	573	38%	415	25%	428	22%
FoNS8	80	5%	0	0%	0	0%
FoNS+	510	34%	551	33%	577	30%
Non-numeric	245	16%	417	25%	587	30%

Figure 1. Comparing year 1 textbooks with respect to FoNS using moving averages.

Figure 2. Data smoothing with moving averages and with adapted Lorenz-curves.

Figure 3. Generating pairwise data from disjoint sections.

Figure 4. Generating pairwise data from moving averages.

Figure 5. Euclidean similarity between Singma & Abacus.

Figure 6. Euclidean similarity between Singma & MNP.

Figure 7. Euclidean similarity between Abacus & MNP.

Figure 8. Pearson correlation between Singma & Abacus.