ABOUT THE SPEAKER
Talithia Williams - Statistician
Talithia Williams builds statistical models that study the spatial and temporal structure of data.

Why you should listen

Dr. Talithia Williams is an Associate Professor of Mathematics at Harvey Mudd College. Her professional experiences include research appointments at the Jet Propulsion Laboratory (JPL), the National Security Agency (NSA), and NASA. Dr. Williams develops statistical models that emphasize the spatial and temporal structure of data with environmental applications. She has been recognized for the development of a cataract model used to predict the cataract surgical rate for developing countries in Africa.

In addition to her academic accomplishments, Dr. Williams and her husband, Donald, actively teach and share foundational principles regarding the joys of Christian marriage. Dr. Williams’ talk will explore how each of us can begin to collect data about ourselves that can provide insight into our personal health.

More profile about the speaker
Talithia Williams | Speaker | TED.com
TEDxClaremontColleges

Talithia Williams: Own your body's data

Filmed:
1,717,214 views

The new breed of high-tech self-monitors (measuring heartrate, sleep, steps per day) might seem targeted at competitive athletes. But Talithia Williams, a statistician, makes a compelling case that all of us should be measuring and recording simple data about our bodies every day — because our own data can reveal much more than even our doctors may know.
- Statistician
Talithia Williams builds statistical models that study the spatial and temporal structure of data. Full bio

Double-click the English transcript below to play the video.

00:12
As a kid I always loved information
0
860
2879
00:15
that I could get from data
1
3739
1848
00:17
and the stories that could be told with numbers.
2
5587
3042
00:20
I remember, growing up, I'd be frustrated at
3
8629
2284
00:22
how my own parents would lie to me using numbers.
4
10913
5546
00:28
"Talithia, if I've told you once
I've told you a thousand times."
5
16459
4984
00:33
No dad, you've only told me 17 times
6
21443
3892
00:37
and twice it wasn't my fault. (Laughter)
7
25335
3162
00:40
I think that is one of the reasons I got a Ph.D. in statistics.
8
28497
3164
00:43
I always wanted to know,
9
31661
908
00:44
what are people trying to hide with numbers?
10
32569
3186
00:47
As a statistician,
11
35755
1183
00:48
I want people to show me the data
12
36938
3853
00:52
so I can decide for myself.
13
40791
2335
00:55
Donald and I were pregnant with our third child
14
43126
3049
00:58
and we were at about 41 and a half weeks,
15
46175
2734
01:00
what some of you may refer to as being overdue.
16
48909
3377
01:04
Statisticians, we call that
17
52286
1835
01:06
being within the 95 percent confidence interval.
18
54121
2686
01:08
(Laughter)
19
56807
1866
01:10
And at this point in the process
20
58673
2278
01:12
we had to come in every couple of days
21
60951
2193
01:15
to do a stress test on the baby,
22
63144
1808
01:16
and this is just routine,
23
64952
1182
01:18
it tests whether or not the baby
is feeling any type of undue stress.
24
66134
4586
01:22
And you are rarely, if ever, seen by your actual doctor,
25
70720
3393
01:26
just whoever happens to be
working at the hospital that day.
26
74113
3167
01:29
So we go in for a stress test and after 20 minutes
27
77280
2746
01:32
the doctor comes out and he says,
28
80026
3498
01:35
"Your baby is under stress, we need to induce you."
29
83524
5555
01:41
Now, as a statistician, what's my response?
30
89079
4619
01:45
Show me the data!
31
93698
3672
01:49
So then he proceeds to tell us
32
97370
2702
01:52
the baby's heart rate trace went from 18 minutes,
33
100072
2425
01:54
the baby's heart rate was in the normal zone
34
102497
1971
01:56
and for two minutes it was in what appeared to be
35
104468
2953
01:59
my heart rate zone and I said,
36
107421
3710
02:03
"Is it possible that maybe this was my heart rate?
37
111131
2366
02:05
I was moving around a little bit,
38
113497
1995
02:07
it's hard to lay still on your back,
39
115492
2298
02:09
41 weeks pregnant for 20 minutes.
40
117790
2518
02:12
Maybe it was shifting around."
41
120308
2173
02:14
He said, "Well, we don't want to take any chances."
42
122481
4976
02:19
I said okay.
43
127457
1260
02:20
I said, "What if I was at 36 weeks
44
128717
1719
02:22
with this same data?
45
130436
1809
02:24
Would your decision be to induce?"
46
132245
3879
02:28
"Well, no, I would wait until you were at least
47
136124
3568
02:31
38 weeks, but you are almost 42,
48
139692
2010
02:33
there is no reason to leave that baby inside,
49
141702
2007
02:35
let's get you a room."
50
143709
1951
02:37
I said, "Well, why don't we just do it again?
51
145660
6581
02:44
We can collect more data.
52
152241
1721
02:45
I can try to be really still for 20 minutes.
53
153962
2411
02:48
We can average the two and see
54
156373
2683
02:51
what that means. (Laughter)
55
159056
2682
02:53
And he goes,
56
161738
3647
02:57
"Ma'am, I just don't want you to have a miscarriage."
57
165385
7049
03:04
That makes three of us.
58
172434
3132
03:07
And then he says,
59
175566
1154
03:08
"Your chances of having a miscarriage double
60
176720
4118
03:12
when you go past your due date. Let's get you a room."
61
180838
3767
03:16
Wow. So now as a statistician, what's my response?
62
184605
6287
03:22
Show me the data!
63
190892
1348
03:24
Dude, you're talking chances,
64
192240
1205
03:25
I do chances all day long, tell me all about chances.
65
193445
2256
03:27
Let's talk chances. (Laughter)
66
195701
1822
03:29
Let's talk chances.
67
197523
1965
03:31
So I say, "Okay, great.
68
199488
1201
03:32
Do I go from a 30-percent
chance to a 60-percent chance?
69
200689
3901
03:36
Where are we here with this miscarriage thing?
70
204590
2551
03:39
And he goes, "Not quite, but it doubles,
71
207141
3296
03:42
and we really just want what's best for the baby."
72
210437
4982
03:47
Undaunted, I try a different angle.
73
215419
2163
03:49
I said, "Okay, out of 1,000 full-term pregnant women,
74
217582
5507
03:55
how many of them are going to miscarry
75
223089
2527
03:57
just before their due date?
76
225616
1795
03:59
And then he looks at me and looks at Donald,
77
227411
2848
04:02
and he goes, about one in 1,000.
78
230259
4703
04:06
I said, "Okay, so of those 1,000 women, how many
79
234962
2830
04:09
are going to miscarry just after their due date?"
80
237792
4858
04:14
"About two." (Laughter)
81
242650
3572
04:18
I said, "Okay, so you are telling me that my chances
82
246222
2044
04:20
go from a 0.1-percent chance
83
248266
3947
04:24
to a 0.2-percent chance."
84
252213
4246
04:28
Okay, so at this point the data is not convincing us
85
256459
2298
04:30
that we need to be induced,
86
258757
1628
04:32
and so then we proceed to have a conversation
87
260385
1949
04:34
about how inductions lead to a higher rate
88
262334
2648
04:36
of Cesarean sections, and if at all
possible we'd like to avoid that.
89
264982
3991
04:40
And then I said,
90
268973
1252
04:42
"And I really don't think my due date is accurate."
91
270225
2880
04:45
(Laughter)
92
273105
2600
04:47
And so this really stunned him
93
275705
2740
04:50
and he looked sort of puzzled
94
278445
1650
04:52
and I said, "You may not know this,
95
280095
2132
04:54
but pregnancy due dates are calculated
96
282227
1581
04:55
assuming that you have a standard 28-day cycle,
97
283808
2538
04:58
and my cycle ranges —
98
286346
1402
04:59
sometimes it's 27, sometimes it's up to 38 —
99
287748
3547
05:03
and I have been collecting the data to prove it.
100
291295
3154
05:06
(Laughter)
101
294449
3784
05:10
And so we ended up leaving the hospital
that day without being induced.
102
298233
5837
05:16
We actually had to sign a waiver
to walk out of the hospital.
103
304070
6193
05:22
And I'm not advocating that you not listen to your doctors,
104
310263
3688
05:25
because even with our first child,
105
313951
1918
05:27
we were induced at 38 weeks; cervical fluid was low.
106
315869
3642
05:31
I'm not anti-medical intervention.
107
319511
2458
05:33
But why were confident to leave that day?
108
321969
2864
05:36
Well, we had data that told a different story.
109
324833
3650
05:40
We had been collecting data for six years.
110
328483
5008
05:45
I had this temperature data,
111
333491
2298
05:47
and it told a different story.
112
335789
1275
05:49
In fact, we could probably pretty
accurately estimate conception.
113
337064
7413
05:56
Yeah, that's a story you want to tell
114
344477
1902
05:58
at your kid's wedding reception. (Laughter)
115
346379
3252
06:01
I remember like it was yesterday.
116
349631
3693
06:05
My temperature was a sizzling 97.8 degrees
117
353324
2641
06:07
as I stared into your father's eyes. (Laughter)
118
355965
4154
06:12
Oh, yeah. Twenty-two more years, we're telling that story.
119
360119
6812
06:18
But we were confident to leave
because we had been collecting data.
120
366931
3051
06:21
Now, what does that data look like?
121
369984
1606
06:23
Here's a standard chart
122
371590
2837
06:26
of a woman's waking body temperature
123
374427
3302
06:29
during the course of a cycle.
124
377729
1517
06:31
So from the beginning of the menstrual cycle
125
379246
1453
06:32
till the beginning of the next.
126
380699
1352
06:34
You'll see that the temperature is not random.
127
382051
2821
06:36
Clearly there is a low pattern
128
384872
2064
06:38
at the beginning of her cycle
129
386936
1999
06:40
and then you see this jump and then a higher
130
388935
2499
06:43
set of temperatures at the end of her cycle.
131
391434
2278
06:45
So what's happening here?
132
393712
1421
06:47
What is that data telling you?
133
395133
2606
06:49
Well, ladies, at the beginning of our cycle,
134
397739
2699
06:52
the hormone estrogen is dominant and that estrogen
135
400438
3342
06:55
causes a suppression of your body temperature.
136
403780
3809
06:59
And at ovulation, your body releases an egg
137
407589
3537
07:03
and progesterone takes over, pro-gestation.
138
411126
5015
07:08
And so your body heats up in anticipation
139
416141
2352
07:10
of housing this new little fertilized egg.
140
418493
3786
07:14
So why this temperature jump?
141
422279
2732
07:17
Well, think about when a bird sits on her eggs.
142
425011
3676
07:20
Why is she sitting on them?
143
428687
1466
07:22
She wants to keep them warm,
144
430153
1937
07:24
protect them and keep them warm.
145
432090
1504
07:25
Ladies, this is exactly what our bodies do every month,
146
433594
2271
07:27
they heat up in anticipation
147
435865
2091
07:29
of keeping a new little life warm.
148
437956
3136
07:33
And if nothing happens, if you are not pregnant,
149
441092
2930
07:36
then estrogen takes back over and
that cycle starts all over again.
150
444022
4542
07:40
But if you do get pregnant, sometimes you
151
448564
1947
07:42
actually see another shift in your temperatures
152
450511
2544
07:45
and it stays elevated for those whole nine months.
153
453055
3287
07:48
That's why you see those pregnant
women just sweating and hot,
154
456342
3325
07:51
because their temperatures are high.
155
459667
3378
07:55
Here's a chart that we had about three or four years ago.
156
463045
4369
07:59
We were really very excited about this chart.
157
467414
2020
08:01
You'll see the low temperature level
158
469434
2536
08:03
and then a shift and for about five days,
159
471970
3042
08:07
that's about the time it takes for the egg to travel
160
475012
2459
08:09
down the fallopian tube and implant,
161
477471
2447
08:11
and then you see those temperatures
start to go up a little bit.
162
479918
3641
08:15
And in fact, we had a second temperature shift,
163
483559
3213
08:18
confirmed with a pregnancy test
that were indeed pregnant
164
486772
4060
08:22
with our first child, very exciting.
165
490832
3081
08:25
Until a couple of days later
166
493913
2031
08:27
I saw some spotting and then I noticed heavy blood flow,
167
495944
4941
08:32
and we had in fact had an early stage miscarriage.
168
500885
4359
08:37
Had I not been taking my temperature
169
505244
3870
08:41
I really would have just thought
my period was late that month,
170
509114
3898
08:45
but we actually had data to show
171
513012
1808
08:46
that we had miscarried this baby,
172
514820
2627
08:49
and even though this data revealed a really
173
517447
1833
08:51
unfortunate event in our lives,
174
519280
1784
08:53
it was information that we could then take to our doctor.
175
521064
2467
08:55
So if there was a fertility issue or some problem,
176
523531
2628
08:58
I had data to show:
177
526159
1255
08:59
Look, we got pregnant, our temperature shifted,
178
527414
2347
09:01
we somehow lost this baby.
179
529761
1684
09:03
What is it that we can do to help prevent this problem?
180
531445
3360
09:06
And it's not just about temperatures
181
534805
3521
09:10
and it's not just about fertility;
182
538326
2741
09:13
we can use data about our bodies to tell us a lot of things.
183
541067
3888
09:16
For instance, did you know that taking
your temperature can tell you a lot
184
544955
3830
09:20
about the condition of your thyroid?
185
548785
2139
09:22
So, your thyroid works a lot like
the thermostat in your house.
186
550924
4015
09:26
There is an optimal temperature
that you want in your house;
187
554939
2218
09:29
you set your thermostat.
188
557157
1524
09:30
When it gets too cold in the house,
your thermostat kicks in
189
558681
2494
09:33
and says, "Hey, we need to blow some heat around."
190
561175
3218
09:36
Or if it gets too hot, your thermostat
191
564393
1669
09:38
registers, "Turn the A.C. on. Cool us off."
192
566062
3557
09:41
That's exactly how your thyroid works in your body.
193
569619
3797
09:45
Your thyroid tries to keep an optimal temperature
194
573416
2700
09:48
for your body.
195
576116
1028
09:49
If it gets too cold, your thyroid
says, "Hey, we need to heat up."
196
577144
2482
09:51
If it gets too hot, your thyroid cools you down.
197
579626
3188
09:54
But what happens when your
thyroid is not functioning well?
198
582814
4406
09:59
When it doesn't function, then it shows up
199
587220
2367
10:01
in your body temperatures,
200
589587
1186
10:02
they tend to be lower than normal or very erratic.
201
590773
2655
10:05
And so by collecting this data
202
593428
1270
10:06
you can find out information about your thyroid.
203
594698
2987
10:09
Now, what is it, if you had a thyroid
problem and you went to the doctor,
204
597685
3564
10:13
your doctor would actually test the amount of
205
601249
2433
10:15
thyroid stimulating hormone in your blood.
206
603682
2938
10:18
Fine. But the problem with that test is
207
606620
4183
10:22
it doesn't tell you how active the hormone is in your body.
208
610803
2765
10:25
So you might have a lot of hormone present,
209
613568
2049
10:27
but it might not be actively working to regulate
210
615617
1748
10:29
your body temperature.
211
617365
1248
10:30
So just by collecting your temperature every day,
212
618613
1749
10:32
you get information about the condition of your thyroid.
213
620362
3620
10:35
So, what if you don't want to take
your temperature every day?
214
623982
2481
10:38
I advocate that you do,
215
626463
1558
10:40
but there are tons of other things you could take.
216
628021
1855
10:41
You could take your blood pressure,
you could take your weight —
217
629876
2805
10:44
yeah, who's excited about
218
632681
1590
10:46
taking their weight every day? (Laughter)
219
634271
3537
10:49
Early on in our marriage, Donald had a stuffy nose
220
637808
4791
10:54
and he had been taking a slew of medications
221
642599
3120
10:57
to try to relieve his stuffy nose, to no avail.
222
645719
3999
11:01
And so, that night he comes and
he wakes me up and he says,
223
649718
4239
11:05
"Honey, I can't breath out of my nose."
224
653957
3807
11:09
And I roll over and I look, and I said,
"Well, can you breath out of your mouth?"
225
657764
4818
11:14
(Laughter)
226
662582
1478
11:16
And he goes, "Yes, but I can't breath out of my nose!"
227
664060
7080
11:23
And so like any good wife, I rush him
228
671140
3020
11:26
to the emergency room
229
674160
1835
11:27
at 2 o'clock in the morning.
230
675995
2432
11:30
And the whole time I'm driving and I'm thinking,
231
678427
3470
11:33
you can't die on me now.
232
681897
2849
11:36
We just got married,
233
684746
2170
11:38
people will think I killed you! (Laughter)
234
686916
4458
11:43
And so, we get to the emergency
room, and the nurse sees us,
235
691374
3673
11:47
and he can't breath out of his nose, and so
236
695047
2621
11:49
she brings us to the back and the doctor says,
237
697668
2083
11:51
"What seems to be the problem?" and
he goes, "I can't breath out of my nose."
238
699751
3189
11:54
And he said, "You can't breath out of your nose?
239
702940
2049
11:56
No, but he can breath out of his mouth. (Laughter)
240
704989
5877
12:02
He takes a step back and he looks at both of us
241
710866
2642
12:05
and he says "Sir, I think I know the problem.
242
713508
3866
12:09
You're having a heart attack.
243
717374
1436
12:10
I'm going to order an EKG and a CAT scan
244
718810
2051
12:12
for you immediately."
245
720861
3342
12:16
And we are thinking,
246
724203
1628
12:17
no, no, no. It's not a heart attack. He can breathe,
247
725831
2940
12:20
just out of his mouth. No, no, no, no, no.
248
728771
4997
12:25
And so we go back and forth with this doctor
249
733768
2263
12:28
because we think this is the incorrect diagnosis,
250
736031
2478
12:30
and he's like, "No really, it'll be fine, just calm down."
251
738509
3952
12:34
And I'm thinking, how do you calm down?
But I don't think he's having a heart attack.
252
742461
3919
12:38
And so fortunately for us, this
doctor was at the end of the shift.
253
746380
3241
12:41
So this new doctor comes in, he sees us clearly
254
749621
2915
12:44
distraught, with a husband who can't breath
255
752536
3001
12:47
out of his nose. (Laughter)
256
755537
3102
12:50
And he starts asking us questions.
257
758639
2786
12:53
He says, "Well, do you two exercise?"
258
761425
4880
12:58
We ride our bikes, we go to the gym occasionally.
259
766305
7073
13:05
(Laughter)
260
773378
1653
13:07
We move around.
261
775031
2865
13:09
And he says, "What were you doing
just before you came here?"
262
777896
2663
13:12
I'm thinking, I was sleeping, honestly.
263
780559
2712
13:15
But okay, what was Donald doing just before?
264
783271
2831
13:18
So Donald goes into this slew
of medications he was taking.
265
786102
3548
13:21
He lists, "I took this decongestant
and then I took this nasal spray,"
266
789650
2962
13:24
and then all of a sudden a lightbulb goes off and he says,
267
792612
1995
13:26
"Oh! You should never mix this
decongestant with this nasal spray.
268
794615
3627
13:30
Clogs you up every time. Here, take this one instead."
269
798242
2817
13:33
He gives us a prescription.
270
801059
2266
13:35
We're looking at each other, and I looked at the doctor,
271
803325
1990
13:37
and I said, "Why is it that it seems like you
272
805315
2226
13:39
were able to accurately diagnose his condition,
273
807541
2411
13:41
but this previous doctor wanted to order
274
809952
2216
13:44
an EKG and a CAT scan?"
275
812168
2506
13:46
And he looks at us and says,
276
814674
2607
13:49
"Well, when a 350-pound man walks in the
emergency room and says he can't breath,
277
817281
4218
13:53
you assume he's having a heart attack
278
821499
1764
13:55
and you ask questions later."
279
823263
3949
13:59
Now, emergency room doctors are
trained to make decisions quickly,
280
827212
5720
14:04
but not always accurately.
281
832932
2091
14:07
And so had we had some information
282
835023
1549
14:08
about our heart health to share with him,
283
836572
2394
14:10
maybe we would have gotten a
better diagnosis the first time.
284
838966
3775
14:14
I want you to consider the following chart,
285
842741
2232
14:16
of systolic blood pressure measurements
286
844973
1954
14:18
from October 2010 to July 2012.
287
846927
4072
14:22
You'll see that these measurements start
288
850999
1693
14:24
in the prehypertension/hypertension zone,
289
852692
3668
14:28
but over about the course of a year and a half
290
856360
2586
14:30
they move into the normal zone.
291
858946
2645
14:33
This is about the heart rate of a healthy 16-year-old.
292
861591
4109
14:37
What story is this data telling you?
293
865700
4031
14:41
Obviously it's the data from someone
294
869731
2881
14:44
who's made a drastic transformation,
295
872612
2673
14:47
and fortunately for us, that person
happens to be here today.
296
875285
5158
14:52
So that 350-pound guy that walked
into the emergency room with me
297
880443
4254
14:56
is now an even sexier and healthier
298
884697
2972
14:59
225-pound guy, and that's his blood pressure trace.
299
887669
6688
15:06
So over the course of that year and a half
300
894357
3461
15:09
Donald's eating changed
301
897818
1569
15:11
and our exercise regimen changed,
302
899387
1991
15:13
and his heart rate responded,
303
901378
2790
15:16
his blood pressure responded to that change
304
904168
1502
15:17
that he made in his body.
305
905670
2299
15:19
So what's the take-home message
306
907969
1978
15:21
that I want you to leave with today?
307
909947
3714
15:25
By taking ownership of your data just like we've done,
308
913661
4374
15:30
just by taking this daily measurements about yourself,
309
918035
3947
15:33
you become the expert on your body.
310
921982
2509
15:36
You become the authority.
311
924491
2002
15:38
It's not hard to do.
312
926493
2423
15:40
You don't have to have a Ph.D. in statistics
313
928916
1920
15:42
to be an expert in yourself.
314
930836
1332
15:44
You don't have to have a medical degree
315
932168
1441
15:45
to be your body's expert.
316
933609
2126
15:47
Medical doctors, they're experts on the population,
317
935735
3419
15:51
but you are the expert on yourself.
318
939154
2278
15:53
And so when two of you come together,
319
941432
1910
15:55
when two experts come together,
320
943342
1970
15:57
the two of you are able to make a better decision
321
945312
2795
16:00
than just your doctor alone.
322
948107
2000
16:02
Now that you understand the power of information
323
950107
3767
16:05
that you can get through personal data collection,
324
953874
1871
16:07
I'd like you all to stand and raise your right hand.
325
955745
3669
16:11
(Laughter)
326
959414
2559
16:13
Yes, get it up.
327
961973
2120
16:18
I challenge you to take ownership of your data.
328
966771
6908
16:25
And today, I hereby confer upon you
329
973679
3562
16:29
a TEDx associate's degree in elementary statistics
330
977241
4345
16:33
with a concentration in time-dependent data analysis
331
981586
4444
16:38
with all the rights and privileges appertaining thereto.
332
986030
3713
16:41
And so the next time you are in your doctor's office,
333
989743
3476
16:45
as newly inducted statisticians,
334
993219
3191
16:48
what should always be your response?
335
996410
2510
16:50
Audience: Show me the data!
Talithia Williams: I can't hear you!
336
998920
1832
16:52
Audience: Show me the data!
337
1000752
1768
16:54
TW: One more time!
338
1002520
1308
16:55
Audience: Show me the data!
339
1003828
1539
16:57
TW: Show me the data.
340
1005367
1182
16:58
Thank you.
341
1006549
3021
17:01
(Applause)
342
1009570
4800

▲Back to top

ABOUT THE SPEAKER
Talithia Williams - Statistician
Talithia Williams builds statistical models that study the spatial and temporal structure of data.

Why you should listen

Dr. Talithia Williams is an Associate Professor of Mathematics at Harvey Mudd College. Her professional experiences include research appointments at the Jet Propulsion Laboratory (JPL), the National Security Agency (NSA), and NASA. Dr. Williams develops statistical models that emphasize the spatial and temporal structure of data with environmental applications. She has been recognized for the development of a cataract model used to predict the cataract surgical rate for developing countries in Africa.

In addition to her academic accomplishments, Dr. Williams and her husband, Donald, actively teach and share foundational principles regarding the joys of Christian marriage. Dr. Williams’ talk will explore how each of us can begin to collect data about ourselves that can provide insight into our personal health.

More profile about the speaker
Talithia Williams | Speaker | TED.com