The word is has not been omitted here. This is an error in analysis.

You’re asking why something that didn’t happen did happen. Your question cannot be directly answered because it includes a false supposition.

Just because a verb has two different arguments beyond the subject doesn’t mean that you need to pretend there is some “missing” word that some “better” writer (or less slovenly, more serious, better educated, more formal, less casual, more careful) would “surely” never have omitted.

This is not a matter of elision, let alone of correctness or respectfulness; rather, it is a matter of syntax. For example, none of these need be rewritten to have any “missing” connective words in them:

1. The bears found us sound asleep in our tents.
2. I found their intrusion unsettling.
3. We’ll just have to find them a new home.
4. Some prefer their pizza cold.
5. But I like mine hot.
6. So the kitchen made me a new pizza.
7. Nightly pizza made me a fat pig.

In particular, verbs like think, feel, believe, regard, consider, judge, find, leave, hold, expect, suppose, and many others all admit transitive senses where the subject imputes to the object some imagined or intended or resulting condition or state, occasionally even a second object as in The madman thought himself the king.

In the particular case of the verb think such as you have asked about here, the OED has an entire section devoted to these senses. Here is a tiny excerpt:

III. With emphasis on an opinion, judgement, or expectation resulting from the action.

11. a. transitive. To hold as an opinion, to believe, judge, consider. Usually: to believe without any great assurance, to regard as likely, to have the idea, to suppose; in reference to a future event: to expect (coinciding partly in meaning with sense 12).

12. To believe or consider something to be possible or likely; to suspect; to expect, anticipate.

a. transitive. With infinitive.

b. transitive. With simple object.

13. With complement.

a. transitive.

(a) With or without to be: to believe, consider, or suppose (someone or something) to be; to look upon as.

(b) With following infinitive other than to be: to suppose (someone or something) to do something. Chiefly, and now only, in passive.

14. To have a particular (good, bad, or other) opinion of a person or thing; to value or esteem something (highly or otherwise).

a. transitive. With quantifier or equivalent noun phrase as object.

Remember that this isn’t something that happens with think alone: quite a few other verbs work the same way as think does here.

The word is has not been omitted from the sample sentence. This is an error in analysis.

You’re asking why something that didn’t happen did happen. Your question cannot be directly answered because it includes a false supposition.

Just because a verb has two different arguments beyond the subject doesn’t mean that you need to pretend there is some “missing” word that some “better” writer (or less slovenly, more serious, better educated, more formal, less casual, more careful) would “surely” never have omitted.

This is not a matter of elision, let alone of correctness or respectfulness; rather, it is a matter of syntax. For example, none of these need be rewritten to have any “missing” connective words in them:

1. The bears found us sound asleep in our tents.
2. I found their intrusion unsettling.
3. We’ll just have to find them a new home.
4. Some prefer their pizza cold.
5. But I like mine hot.
6. So the kitchen made me a new pizza.
7. Nightly pizza made me a fat pig.

In particular, verbs like think, feel, believe, regard, consider, judge, find, leave, hold, expect, suppose, and many others all admit transitive senses where the subject imputes to the object some imagined or intended or resulting condition or state, occasionally even a second object as in The madman thought himself the king.

In the particular case of the verb think such as you have asked about here, the OED has an entire section devoted to these senses. Here is a tiny excerpt:

III. With emphasis on an opinion, judgement, or expectation resulting from the action.

11. a. transitive. To hold as an opinion, to believe, judge, consider. Usually: to believe without any great assurance, to regard as likely, to have the idea, to suppose; in reference to a future event: to expect (coinciding partly in meaning with sense 12).

12. To believe or consider something to be possible or likely; to suspect; to expect, anticipate.

a. transitive. With infinitive.

b. transitive. With simple object.

13. With complement.

a. transitive.

(a) With or without to be: to believe, consider, or suppose (someone or something) to be; to look upon as.

(b) With following infinitive other than to be: to suppose (someone or something) to do something. Chiefly, and now only, in passive.

14. To have a particular (good, bad, or other) opinion of a person or thing; to value or esteem something (highly or otherwise).

a. transitive. With quantifier or equivalent noun phrase as object.

Remember that this isn’t something that happens with think alone: quite a few other verb“s work the same way as think does here.

It has not been omitted. Just because a verb has two different arguments beyond the subject doesn’t mean that you need to pretend there is some “missing” word that some “better” writer (or less slovenly, more serious, better educated, more formal, less casual, more careful) would “surely” never have omitted.

This is not a matter of elision, let alone of correctness or respectfulness; rather, it is a matter of syntax. For example, none of these need be rewritten to have any “missing” connective words in them:

1. The bears found us sound asleep in our tents.
2. I found their intrusion unsettling.
3. We’ll just have to find them a new home.
4. Some prefer their pizza cold.
5. But I like mine hot.
6. So the kitchen made me a new pizza.
7. Nightly pizza made me a fat pig.

In particular, verbs like think, feel, believe, regard, consider, judge, find, leave, hold, expect, suppose, and many others all admit transitive senses where the subject imputes to the object some imagined or intended or resulting condition or state, occasionally even a second object as in The madman thought himself the king.

In the particular case of the verb think such as you have asked about here, the OED has an entire section devoted to these senses. Here is a tiny excerpt:

III. With emphasis on an opinion, judgement, or expectation resulting from the action.

11. a. transitive. To hold as an opinion, to believe, judge, consider. Usually: to believe without any great assurance, to regard as likely, to have the idea, to suppose; in reference to a future event: to expect (coinciding partly in meaning with sense 12).

12. To believe or consider something to be possible or likely; to suspect; to expect, anticipate.

a. transitive. With infinitive.

b. transitive. With simple object.

13. With complement.

a. transitive.

(a) With or without to be: to believe, consider, or suppose (someone or something) to be; to look upon as.

(b) With following infinitive other than to be: to suppose (someone or something) to do something. Chiefly, and now only, in passive.

14. To have a particular (good, bad, or other) opinion of a person or thing; to value or esteem something (highly or otherwise).

a. transitive. With quantifier or equivalent noun phrase as object.

Remember that this isn’t something that happens with think alone: quite a few other verbs work the same way as think does here.

The word is has not been omitted here. This is an error in analysis.

You’re asking why something that didn’t happen did happen. Your question cannot be directly answered because it includes a false supposition.

Just because a verb has two different arguments beyond the subject doesn’t mean that you need to pretend there is some “missing” word that some “better” writer (or less slovenly, more serious, better educated, more formal, less casual, more careful) would “surely” never have omitted.

This is not a matter of elision, let alone of correctness or respectfulness; rather, it is a matter of syntax. For example, none of these need be rewritten to have any “missing” connective words in them:

1. The bears found us sound asleep in our tents.
2. I found their intrusion unsettling.
3. We’ll just have to find them a new home.
4. Some prefer their pizza cold.
5. But I like mine hot.
6. So the kitchen made me a new pizza.
7. Nightly pizza made me a fat pig.

In particular, verbs like think, feel, believe, regard, consider, judge, find, leave, hold, expect, suppose, and many others all admit transitive senses where the subject imputes to the object some imagined or intended or resulting condition or state, occasionally even a second object as in The madman thought himself the king.

In the particular case of the verb think such as you have asked about here, the OED has an entire section devoted to these senses. Here is a tiny excerpt:

III. With emphasis on an opinion, judgement, or expectation resulting from the action.

11. a. transitive. To hold as an opinion, to believe, judge, consider. Usually: to believe without any great assurance, to regard as likely, to have the idea, to suppose; in reference to a future event: to expect (coinciding partly in meaning with sense 12).

12. To believe or consider something to be possible or likely; to suspect; to expect, anticipate.

a. transitive. With infinitive.

b. transitive. With simple object.

13. With complement.

a. transitive.

(a) With or without to be: to believe, consider, or suppose (someone or something) to be; to look upon as.

(b) With following infinitive other than to be: to suppose (someone or something) to do something. Chiefly, and now only, in passive.

14. To have a particular (good, bad, or other) opinion of a person or thing; to value or esteem something (highly or otherwise).

a. transitive. With quantifier or equivalent noun phrase as object.

Remember that this isn’t something that happens with think alone: quite a few other verbs work the same way as think does here.