You can label the points in a Google ScatterChart by adding a tooltip. Tooltips show up when you mouseover a data point.
The code for your data table should look something like this:
var dt = new google.visualization.DataTable(
{
cols: [{id: 'A', label: 'Age', type: 'number'},
{id: 'B', label: 'Response', type: 'number'},
{id: 'C', label: 'Name', type:'tooltip', p:{role:'tooltip'}}
],
rows: [{c:[{v: 12}, {v: 40}, {v:'Allen'}]},
{c:[{v: 16}, {v: 45}, {v:'Tom'}]},
{c:[{v: 17}, {v: 60}, {v:'Sim'}]}
]
},
0.6
)
When you mouseover the points, the name will show up.
Link to Tooltips:
https://developers.google.com/chart/interactive/docs/roles#tooltiprole
Link to DataTable class (for formatting data):
https://developers.google.com/chart/interactive/docs/reference#DataTable
NOTE: if you're trying to plot multiple data series, you have to specify a tooltip for each one. For example, if you add a separate data series for Average Response, the code would change to:
var dt = new google.visualization.DataTable(
{
cols: [{id: 'A', label: 'Age', type: 'number'},
{id: 'B', label: 'Response', type: 'number'},
{id: 'C', label: 'Name', type:'tooltip', p:{role:'tooltip'}},
{id: 'D', label: 'AvgResp', type: 'number'},
{id: 'E', label: 'Category', type:'tooltip', p:{role:'tooltip'}}
],
rows: [{c:[{v: 12}, {v: 40}, {v:'Allen'}, {v:null}, {v:null}]},
{c:[{v: 16}, {v: 45}, {v:'Tom'}, {v:null}, {v:null}]},
{c:[{v: 17}, {v: 60}, {v:'Sim'}, {v:null}, {v:null}]},
{c:[{v: 12}, {v: null}, {v:null}, {v: 35}, {v:'Avg. 12yo'}]},
{c:[{v: 16}, {v: null}, {v:null}, {v: 48}, {v:'Avg. 16yo'}]},
{c:[{v: 17}, {v: null}, {v:null}, {v: 52}, {v:'Avg. 17yo'}]}
]
},
0.6
)