## Number Line Estimation

## Factors Related to Number Line Estimation Performance

## Number Line Estimation in WS and DS

## The Current Study

## Method

### Participants

### Materials and Procedure

#### Number Line Estimation

#### Number Familiarity

### Procedure

#### Preliminary Data Computation

## Results

TD | WS | DS | ||||
---|---|---|---|---|---|---|

N | M (SD) | N | M (SD) | N | M (SD) | |

Age | 25 | 74.0 (18.8) | 28 | 244.7 (160.9) | 25 | 258.4 (128.6) |

Non-verbal IQ | 25 | 17.3 (5.8) | 28 | 15.6 (4.5) | 25 | 15.8 (6.4) |

Mathematical achievement | 25 | 11.0 (7.2) | 28 | 8.6 (3.7) | 25 | 8.2 (3.0) |

Visuo-spatial skills | 21 | 103.1 (26.2) | 28 | 65.7 (31.0) | 22 | 84.2 (22.5) |

Number familiarity | 25 | 76.2 (23.5) | 28 | 86.1 (17.3) | 25 | 67.6 (21.9) |

PAE 0–10 | 25 | 13.8 (9.4) | 28 | 16.3 (8.8) | 25 | 18.7 (12.6) |

PAE 0–100 | 24 | 22.8 (13.4) | 26 | 22.1 (9.0) | 23 | 25.6 (12.1) |

\( {\text{R}}^{ 2}_{\text{Lin}} \) 0–10 | 25 | .8 (.3) | 28 | .7 (.3) | 25 | .7 (.3) |

\( {\text{R}}^{ 2}_{\text{Lin}} \) 0–100 | 24 | .5 (.4) | 26 | .5 (.3) | 23 | .3 (.3) |

_{p}

^{2}= .3, with the TD group being significantly younger than both the WS (MD = − 170.6 months, p < .001) and DS groups (MD = − 184.4 months, p < .001). There was a significant main effect of group on visuo-spatial skills, F(2,68) = 11.4, p < .001, n

_{p}

^{2}= .3, with the TD group having significantly better visuo-spatial skills than the DS group (MD = 18.9, p = .026) and the DS having significantly better visuo-spatial skills than the WS group (MD = 18.6, p < .001). There was also a significant main effect of group on number familiarity, F(2,73) = 5.2, p = .008, n

_{p}

^{2}= .1, with the WS group scoring significantly higher in the number familiarity task than the DS group (MD = 18.6, p = .002). There was no significant main effect of group for non-verbal IQ or mathematical achievement. These findings confirm different cognitive profiles for individuals with WS and DS despite being matched on overall IQ.

### Differences in Number Line Estimation

_{10}= .194; 0–100 PAE: BF

_{10}= .334; 0–10 \( {\text{R}}^{ 2}_{\text{Lin}} \): BF

_{10}= .328; 0–100 \( {\text{R}}^{ 2}_{\text{Lin}} \): BF

_{10}= .188). Therefore, there was no significant difference between groups in their performance on the number line task, independent of metric or scale, and these frequentist statistics were supported by Bayesian analyses.

### Relationship Between Number Line Estimation and Mathematical Achievement

TD | WS | DS | |
---|---|---|---|

PAE 0–10 | − .644** | − .404* | − .531** |

PAE 0–100 | − .772** | − .577** | − .658** |

\( {\text{R}}^{ 2}_{\text{Lin}} \) 0–10 | .497* | .492** | .488* |

\( {\text{R}}^{ 2}_{\text{Lin}} \) 0–100 | .785** | .548** | .423* |

### Relationship Between Visuo-spatial Skills and Number Familiarity with Number Line Estimation Performance

TD | WS | DS | |
---|---|---|---|

r | r | r | |

PAE 0–10 | − .560* | − .189 | − .556* |

PAE 0–100 | − .708** | − .299 | − .478* |

TD | WS | DS | |
---|---|---|---|

r | r | r | |

PAE 0–10 | − .508* | − .593* | − .367 |

PAE 0–100 | − .807** | − .509* | − .436* |

### Predictors for Number Line Estimation Performance in WS, DS and TD Group

TD | WS | DS | |
---|---|---|---|

r | r | r | |

Adjusted R ^{2} | .379* | .299* | .237* |

Predictors | |||

Visuo-spatial skills | − .273 | .006 | − .534* |

Number familiarity | − .461 | − .594* | − .038 |

TD | WS | DS | |
---|---|---|---|

r | r | r | |

Adjusted R ^{2} | .725** | .218* | .222* |

Predictors | |||

Visuo-spatial skills | − .302 | − .144 | − .366 |

Number familiarity | − .647* | − .461* | − .295 |